unit e: planet earth - who are we...

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Name _________________________ Date_______________ Unit E: Planet Earth 1.0 Earth’s surface undergoes gradual and sudden changes. Read Through pages 353 – 367 and fill in the notes. 1.1 A Model for Earth A Model is an ____________ of something that can’t be fully _____________ or ____________. Models are useful when something is too ___________ or too ________________ for us to study easily. An example of a model for the Earth is a ______________. What’s Inside the Earth? _____________________ are scientists who study the _____________. Geologists use ______________ to study the Earth and determine the inner structure. From what they have studied, the Earth seems to be made up of ____ ___________ _______________. Science 7 – Unit E: Planet Earth Page 1 of 43

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Name _________________________ Date_______________

Unit E: Planet Earth

1.0 Earth’s surface undergoes gradual and sudden changes. Read Through pages 353 – 367 and fill in the notes.

1.1 A Model for Earth

A Model is an ____________ of something that can’t be fully _____________ or ____________. Models are useful when something is too ___________ or too ________________ for us to study easily.An example of a model for the Earth is a ______________.

What’s Inside the Earth?_____________________ are scientists who study the _____________. Geologists use ______________ to study the Earth and determine the inner structure. From what they have studied, the Earth seems to be made up of ____ ___________ _______________.

Layers of the Earth Characteristics

Science 7 – Unit E: Planet Earth Page 1 of 36

Name _________________________ Date_______________

Assignment: Complete Check and Reflect #1-3 on page 356.

1.2 Sudden Earth Changes

What Causes Earthquakes?

Science 7 – Unit E: Planet Earth Page 2 of 36

Name _________________________ Date_______________

Earthquakes are:

… and are caused by the:

This sudden break causes the earthquake.

The First BreakThe focus is the…

The sudden breaking of rocks at the focus ___________ ________________ that spreads as ______________ through the Earth.

These waves are called __________________ _____________ (from the Greek word “seismos,” meaning “earthquake”).

What causes the earth to shake?

These waves are used by ___________________ to study the Earth’s ___________.

Because of the effect an earthquake can have on the _______________ of the Earth, geologists look for it’s ____________________.

This is the…

Measuring the Strength of Earthquakes

Geologists have developed various _____________ to determine the _______________ or ____________________ of an earthquake.

Science 7 – Unit E: Planet Earth Page 3 of 36

Name _________________________ Date_______________

The magnitude of an earthquake is given as a number on the _________________.

What was the name of the scientist who developed this scale?

Take a look at table below; compare the magnitudes of earthquakes with their frequency. Is there a pattern? Explain.

If every number on the Richter scale means an increase in magnitude of 10, what is the power of a Richter 4?

Richter 8?

Volcanoes

A volcano is…

Science 7 – Unit E: Planet Earth Page 4 of 36

Richter Scale Magnitudes

Magnitude Number Per Year (World)2 Just felt more than 100,0004.5 Damage begins a few 1,0007 "Major" 16 to 188 "Great" 1 or 28.6 Maximum recorded

Some Representative MagnitudesYear Location Magnitude1906 San Francisco 8.251960 Chile 8.51964 Alaska 8.61970 Peru 7.751971 San Fernando Valley, CA 6.41972 Nicaragua 6.21976 Guatemala 7.91976 China 7.61977 Romania 7.21995 Kobe, Japan 6.9

Name _________________________ Date_______________

Using Figure 1.10 on page 360, fill in the boxes with a brief description of what happens when a volcano erupts:

Check out National Geographic Explorers @

http://magma.nationalgeographic.com/ngexplorer/0405/quickflicks/ for more info Volcanoes!

Tools and Techniques for Studying Earth

Using the diagrams on page 361, fill in the following chart:

Science 7 – Unit E: Planet Earth Page 5 of 36

Name _________________________ Date_______________

Tool Used Description Function

Fireproof suit

Seismograph

Surveyor’s Level

Are there any more tools that you can find in the library and internet??...

Assignment: Page 362, Check and Reflect 1 – 3, and 5.

Science 7 – Unit E: Planet Earth Page 6 of 36

Name _________________________ Date_______________

In groups of 2 - 3, you are going to make a poster of an earthquake or volcanic eruption from history. The poster will be on poster board (supplied to you) and will consist of various facts and pictures of the natural occurrence including:

Date and location

Magnitude of earthquake/eruption

Severity of disaster

Were there any warning signs? If so, what were they?

You will be given one class period to organize your group and spend some time in the library conducting some research. You should use the resources in the library such as; atlases, history references, encyclopedias, almanacs, magazines (e.g. National Geographic), and the internet.

Another class period will be assigned to put your posters together and will be due at the end of the class.

Try to get together with your group members at lunch, after school or in the evening to make your poster the best it can be.

Ideas for your poster:Find pictures from magazines that you can cut out (ask for permission first!!!)Maps, statistics and any extra “Interesting Facts” are a great addition.REMEMBER: It’s the value of the information that counts, not just the visual appeal of your poster

1.3 Incremental changes: wind, water, and ice

Science 7 – Unit E: Planet Earth Page 7 of 36

Name _________________________ Date_______________

Earthquakes and volcanoes are sudden and catastrophic. The ________________ and __________________ of the Earth’s surface is accomplished by the combination of ___________, step-by-step changes called ____________________ and _____________.

Weathering is the…

Erosion is the…

Deposition is the…

Throughout these processes materials are neither gained nor lost, it simply _________________ ____________.

Can you think of some materials found on the Earth that have changed shape over the years? (Example: Did you know that glass is sand that has changed because of extremely high temperatures?) List them here.

Science 7 – Unit E: Planet Earth Page 8 of 36

Name _________________________ Date_______________

Using pages 363 – 364 in your textbook, fill in the following chart.

Type of Weathering

Types of Forces Responsible Example

The Effects of Moving Water

______________ and ______________ are probably the most powerful forces of _____________ that alter the landscape. As rivers flow, they carry a load of _________, _________, and ____________, called sediment. Sedimentation is the process of

Landforms are frequently created by running water; these types of landforms are called _________________________.

Eroding Away

Science 7 – Unit E: Planet Earth Page 9 of 36

Name _________________________ Date_______________

Remember…erosion is the transfer of materials of weathering from one place to another. One very powerful and potentially dangerous form of water erosion is a ______________________. Where there is a sudden and fast movement of rocks and soil down a slope.

Can you think of ways that landslides can be prevented? Think of the homes long the riverbank, or the roads that go through the mountains, is there evidence of landslides being prevented?

Glaciers – Rivers of Ice

A _________________ is a moving mass of ice and snow. As _________________ flow, they pick up large

Science 7 – Unit E: Planet Earth Page 10 of 36

October 23, 1999.

Houses cling to the remaining riverbank after a 1999 landslide sent one home along Whitemud Road tumbling down.

Independent scientists on board a Greenpeace ship found last month that the glacier, located in eastern Greenland, is moving at a speed of 14 kilometers per year, compared to five kilometers per year in 1988.~physorg.com

Name _________________________ Date_______________

________ _________________ that act as grinding tools to carve and scrape the ground beneath them.

Erosion occurs when the _____________ gathers large rocks and drags them along its base. Doing this the glacier grinds the __________________. This is the _____________________________________________________________________________________________. The glacier then melts or _______________, and leaves behind a sculpted landscape.

When huge boulders and rocks are carried by the glacier from one area to another, this is called?

These deposits result in three types of landforms, list them.

Assignment: Assess Your Learning, page 367, # 1 – 10

2.0 The Rock Cycle describes how rocks form and change over time.

2.1 What are rocks and minerals?

Minerals in Rocks

Science 7 – Unit E: Planet Earth Page 11 of 36

Photo: Muddy River Glacier snakes through the mountains near Frederick Sound, British Columbia, (United States Navy photograph at the World Data Center for Glaciology, Boulder)

Check out National Geographic Explorers @

http://magma.nationalgeographic.com/ngexplorr/0501/quickflicks/ for

more info on Glaciers!Section 1.0

Quiz!!! Coming Soon…

Name _________________________ Date_______________

All rocks are made up of tiny particles called ________________. The building blocks for rocks are pure substances called _________________, and all rocks are made of them. There are two basic types of rocks, one type is made of one mineral, and example of this is? __________________. The other type is made of two or more minerals, and example of these rocks is ________________.

So far there are __________ types of minerals that have been identified, and are called by their common names.The earth is composed of 5 main minerals:

1.____________

2.____________

3.____________

4.____________

5._____________

Using Properties to Identify MineralsProperties are

Mineral Property Characteristic

Science 7 – Unit E: Planet Earth Page 12 of 36

Check out The Mineral and Gemstone Kingdom @

http://www.minerals.net/resource/property/properti.htm to see

all the properties used to identify minerals!

Name _________________________ Date_______________

Is the streak powder always the same color as the mineral? ___________________What is the difference between cleavage and fracture?

The Mohs scale of hardness lists 10 minerals ranked by hardness; with _____________ as the hardest mineral, ________________ as the softest mineral, and _________________ with a hardness of 6. Most rocks can be identified using three types of

guidelines:

1. 2.3.

Prospecting for Wealth

Science 7 – Unit E: Planet Earth Page 13 of 36

Dentist’s drills have tiny bits of Diamonds

imbedded in their tools. Since it is the hardest mineral, it is the only material that is hard

enough to grin past your enamel!

… So next time someone says you have a “Million Dollar Smile!”… you can

say, “Why yes it is!! Thank you!”

Name _________________________ Date_______________

Canada: A Diamond-Producing Nation

For many years, the thought of finding diamonds in Canada was little more than a prospector’s dream. But that dream became a reality following the discovery, in the 1990s, of several world-class diamond-bearing deposits in Canada’s north.

Diamond exploration began in Canada as early as the 1960s but major kimberlite discoveries were not made until the 1980s. In 1991, the first economic diamond deposit was discovered in the Lac de Gras area of the Northwest Territories. Canada became a diamond producer in October 1998 when the Ekati diamond mine opened about 300 kilometres northeast of Yellowknife. By April 1999, the mine had produced one million carats.

Canadian Diamond IndustryCanada’s diamond industry has now become an industry worth more than $2.0 billion with all indicators pointing to potential for future growth. Canadian diamond production in 2003 was about 11.6 million carats and in 2004 was 12.6 million carats.

Diavik, Canada’s second diamond mine, began production in January 2003. During its projected 20-year life, average diamond production from this mine is expected to peak at six to eight million carats a year — about five percent of the world’s total supply. Ekati’s average production over its projected 20-year life is expected to peak at three to five million carats a year — four percent of world production by volume.

Another three mines are scheduled to open by 2008: one at Snap Lake, about 220 kilometres northeast of Yellowknife, N.W.T.; Victor, near James Bay in Ontario; and Jericho in Nunavut. These mines will consolidate Canada’s position in world diamond production by value, third after Botswana and Russia

http://www.nrcan.gc.ca/mms/diam/index_e.htm

As you can see, Canada has developed a large industry in terms of rocks and minerals, Ekati diamonds being a recent investment. Canada, however has been mining rocks and minerals for years, which is now developed into a $50 billion industry!

List the minerals that Canada exports and produces:

What is Alberta’s main export?2.2 Three classes of rocks: igneous, sedimentary, and

metamorphic

Science 7 – Unit E: Planet Earth Page 14 of 36

Name _________________________ Date_______________

Can you list the 3 classes of rocks?

1.

2.

3.

Copy out the diagram on page 377 in your textbook. Make the diagram clear and simple as possible so that you can add to the diagram as we go along.

Rocks are organized into three main families, what determines this classification?

Science 7 – Unit E: Planet Earth Page 15 of 36

Name _________________________ Date_______________

Igneous RocksThe Latin word for igneous is _______________, meaning __________. Knowing this, where are igneous rocks formed? ______________________

Magma, also called __________ ___________, is found in which layer of the Earth? __________________________. This magma can cool in two different places, ___________ the surface of the Earth or ______________ the surface of the Earth. Depending on where the

magma cools, determines what type of rocks will form.

Rock Type Intrusive Rock Extrusive Rock

Characteristics

Examples

Sedimentary RocksThe root word for these types of rocks is “sediment”, which means, _______________________________________________________________________. Sedimentary rocks for when small pieces of __________ are carried by _________ or ___________ and settle and sink down into the rocks below them. This process takes many years to create this type of rock.

Science 7 – Unit E: Planet Earth Page 16 of 36

Name _________________________ Date_______________

What is a key characteristic of sedimentary rocks that is different than igneous?

Many types of sediments come together by wind and water to produce rocks over millions of years, resulting in various types of rocks. Some examples of sediments are; sand, silt, or sea shells… List 4 others.

Metamorphic Rock

From Latin meanings, metamorphic means “______________________”. These rocks began out as _________________, ___________________, ________________. In order to change to shape and form of these rocks requires two conditions, what are they?

Today there are over 3500 different types of rocks that need to be classified, classification means:

Science 7 – Unit E: Planet Earth Page 17 of 36

Most of the rocks on the surface of

the Earth are sedimentary!

Name _________________________ Date_______________

Geology Tools and Techniques

Tool/Technique Description

Assignment: Check and Reflect, p. 384, # 1 – 4.

2.3 The rock cycle

Science 7 – Unit E: Planet Earth Page 18 of 36

Name _________________________ Date_______________

In time everything gets recycled… including rocks! In order for this to happen, the Earth gives itself a little assistance… can you find the three ways in which the weather plays a part in this?1. 2.3.

Just like you recycle paper to create egg cartons or toilet paper… Pop cans are recycled to become plastic lumber or clothing… rocks are also recycled into new rocks. In the space below, copy down the diagram of the rock cycle from page 386 in your textbook.

Alberta’s Landscape

Science 7 – Unit E: Planet Earth Page 19 of 36

Name _________________________ Date_______________

Within Alberta’s geology lie two main layers, describe what each definition is, where these layers are located, and what type of rock families (sedimentary, igneous, metamorphic) compose these layers:

Precambrian Shield

__________________________________________________________________________________________________________________

Interior Plains________________________________________________________________________________________________________________________________________________

Check and Reflect, page 390, # 1 & 2. Assess your Learning, page 391, # 1 – 10.

Time to do some searching on the internet!! There are lots of careers that involve the Planet Earth, and many women in science that study the earth and the way it works! Research the following careers: Volcanologist, Seismologist,

Geologist. Describe the career and what these jobs involve. Find a woman who has a career in these fields, this person can be

famous or a more recent woman who is perusing this career now!

Science 7 – Unit E: Planet Earth Page 20 of 36

Section 2.0 Quiz!!! Coming Soon…

Name _________________________ Date_______________

3.0 Landforms provide evidence of change. 3.1 Continental Drift

How old do you think the Earth is?Do you think it always looked the way it did?What are some pieces of evidence for this?

Continents on the MoveIn 1910, ______________ ______________, a German scientist noticed something about the ____________________. It looked as if they all could fit together like a puzzle! He developed a ___________________ that all the continents at one time had been joined together. What was the name he gave to this land mass and what does the word mean?

He also hypothesized that these continents broke and slowly____________ apart. Today geologists use the term ____________________ __________, to describe this theory. Examine Figure 3.2 in your textbook, and observe the evidence… in the

Science 7 – Unit E: Planet Earth Page 21 of 36

Name _________________________ Date_______________

legend is 4 items that give us an indication that Wegener’s hypothesis may be true. Make four observations using the evidence that would suggest that the continents were once joined.

3.2

3.2 Plate tectonics

Developing a New TheoryRead page 395.

Interpreting the PatternsThe Theory of Plate Tectonics suggests that all the continents were once joined together as one large land mass which Wegener called _________________.; otherwise known as “super continent”. These land masses split and slowly drifted apart. Evidence further supports this theory… Scientists have noticed distinctive deep valleys called _____________, and long underwater mountain ranges called _______________. This explained why volcanoes and earthquakes tend to be in the same areas around the world.

Science 7 – Unit E: Planet Earth Page 22 of 36

Check and Reflect, page 394, # 1 & 2.

Name _________________________ Date_______________

Several other pieces of evidence were gathered that enhanced Wegener’s theory, these were:

Define the Theory of Plate Tectonics

According to the theory, the _______________ (land) is broken up into large pieces. These pieces are called ______________. All the plates are moving very slowly on a ______________________ layer of crust. On the following diagram of the earth, and using figure 3.7 in the textbook, draw the lines of the plates.

Each plate has its own title, usually corresponding to the continent to which it holds, using Figure 3.8 in your textbook, draw in the plate boundaries and label the diagram with the plate names.

Science 7 – Unit E: Planet Earth Page 23 of 36

Name _________________________ Date_______________

Plate BoundariesA boundary is __________________________________________________________.There are three types of boundaries:

1.2.3.

Divergent Boundary (pulling apart)

One example of a diverging boundary is the _____________________________. At this type of boundary, lava flows ________ the ridge to form new ______________ crust. Here volcanoes flow high enough to be ________________.

Convergent Boundary (crashing)

Science 7 – Unit E: Planet Earth Page 24 of 36

Name _________________________ Date_______________

Converging boundaries experience a lot of __________________, since plates are moving into each other. This boundary has two situations:

A)Subduction

- With subducting plates, one plate carries _________________ crust, while the other carries _______________________ crust.

Of the two plates, the thinner plate will be pushed underneath the thicker plate. Which plate is thicker than the other?

- This great force acting on the plates causes what type of natural occurrence? _____________________.

- Another great natural occurrence happens when the oceanic crust is pushed down where it begins to melt and turns into ______________.

- This sometimes causes molten rock to rise and form __________________.

B) DeformationThis type of converging boundary is when two ________________________ crusts collide. In this case, as the two plates crush together, ______________________ will form.

Science 7 – Unit E: Planet Earth Page 25 of 36

Name _________________________ Date_______________

Transforming Boundary (sideswiping)The third type of boundary occurs when plates slide ____________________ past each other. These plates don’t slide smoothly; there is a lot of friction that results in many earthquakes along this line. The most famous transform boundary is the ________________________________, along the west coast of the United States. Summarize what you have learned so far…

Plate Tectonic SummaryMovement

Type

Description

Diagram

Locations on Earth

Now let’s go back to our world map and plot the different plate movements. Create a legend that would distinguish your boundaries.

Science 7 – Unit E: Planet Earth Page 26 of 36

Legend:

Name _________________________ Date_______________

3.3 Mountain Building

A Mountain is a ________________________________________________________________________________________________________________________________________________A mountain range is ________________________________________________________________________What mountain region is the longest in the world? (before looking in the text, think of the name on your own ) _________________________________________

It takes millions of years to create a mountain through the movement of plates, this process is called ____________________________.

Which plate movements do you think are responsible for building mountains? Explain your answer.

Structure and Development of Fold and Fault Mountains

Science 7 – Unit E: Planet Earth Page 27 of 36

Check and Reflect, page 400, # 1, 3 and 4.

Name _________________________ Date_______________

Once mountains are formed, they undergo many changes. As mountains get larger, more and more rock is being added to them, this causes the rocks at the bottom of the mountain to experience a lot of pressure, and this is called ________________ _____________. These forces cause the sedimentary rock to _________ and __________. This is also known as folding and faulting.Folding

There are two types of folding:

A) _________________ - an upfold in the rock.B) _________________ - a downfold in the rock.

Faulting

Most mountains are created by a ____________________ of both processes.

Label the following mountain folds as being either anticline or syncline.

Science 7 – Unit E: Planet Earth Page 28 of 36

Name _________________________ Date_______________

Assignment: Check and Reflect, page 408, # 1 – 3. Assess your Learning, page 409, # 1 – 8.4.0 The fossil record provides evidence of earth’s changes

over time

4.1 Tracing evidence of geological change using fossils

Where does the word fossil come from?

What types of rocks are fossils usually found in and why?

What types of animals make up most fossils?

What types of rocks commonly make up fossils?

Fossils

Fossils are _____________________________________________________________. To become a fossil, an organism (plant or animals) dies and sinks to the

Science 7 – Unit E: Planet Earth Page 29 of 36

Section 3.0 Quiz!!! Coming Soon…

Name _________________________ Date_______________

bottom of a _______________________. They are then ______________ by layers of sediment, and preserved. The organism and the sedimentary rock are the _________ age!

Scientists who study fossils are called __________________________ (watch your spelling!!). A common misconception is that paleontologists are

“dinosaur diggers”; their jobs however involve a lot more. What are some aspects of being a paleontologist?

Becoming a Fossil

Although it seems like there are a lot of fossils, it is actually very rare to become a fossil. There are many ways in which organisms can become fossilized, list the three methods identified in your textbook:

1. 2.3.

A __________ fossil – cavity or track left behind by an organism. Ex. ___________

A __________ fossil – filled-in cavities left by the original organic bodies.

Trees and plants can also leave behind fossils. These are found in the form of ______________ wood or

preserved leaves.

Science 7 – Unit E: Planet Earth Page 30 of 36

Petrified wood is wood that has been preserved for millions of years by the process of petrification. This process turns the wood into quartz crystal, which is very brittle and shatters. Even though petrified wood is fragile, it is also harder than steel!!

Name _________________________ Date_______________

Which scientists use fossils to study Earth’s geological history?

Fossils are mostly made from what kinds of organisms?

The layers that form in sedimentary rocks are called _________________. The layers can tell us about the age of the Earth and what happened in the past. The bottom layers would be the oldest/youngest (circle right answer) and the layers at the top would be the oldest/youngest…

Check and Reflect, page 414, # 1 & 2.

4.2 Methods used to interpret fossils

Examining and interpreting fossils gives us a look back at how life has changed on Earth. Fossils show us a sequence of ________________ __________ _________ appearing through time. Show the sequence of life forms using the information in your textbook…

(Earlier) (Later)

Areas such as The Grand Canyon are excellent places to study the Earth’s history. Why is this, and

what other places around the world are great for studying fossils?

Fossil Beds

Science 7 – Unit E: Planet Earth Page 31 of 36

Name _________________________ Date_______________

When environmental conditions are favorable, many species can be fossilized, which is the case with the Burgess Shale fossil bed in Yoho National Park.

Burgess Shale: a treasure of ancient fossils

The 515 million year-old remains of more than 120 species of marine animals have been found in the Burgess Shale, preserved in exquisite detail. In some cases scientists can even see what these ancient creatures ate just before they died!

Check and Reflect, page 419, # 1 – 3.

4.3 Geologic Time

Most of what scientists used to piece together the Earth’s history has been taken from studying ___________ and _____________ records.This information has been gathered and grouped into geologic time intervals called __________. Scientists have developed a geological time scale that involves 4 major eras. Each era represents a _____________ _____________ in the global environment and is characterized by different ___________ ____________.

Under each era:- indicate time period- major geological changes- types of organisms that existed in that era

Science 7 – Unit E: Planet Earth Page 32 of 36

Where in Canada is Yoho

National Park??

________________

Name _________________________ Date_______________

Group Activity

In groups of 2 – 3, you will be asked to pick one historic event in the history of the Earth and do some research on your event.

You will be presenting your findings on a large piece of construction paper and should include the following:

Name of major eventDate of major eventPictures depicting the event Additional information pertaining to the event such as:

o Species o Scientists who made the discoveryo Where in the world the evidence was foundo What significance this made to the dating of Earth’s

Geological time frame

The historical events that you may choose from are found on page 422 of your textbook. You will have one class period to

Science 7 – Unit E: Planet Earth Page 33 of 36

Name _________________________ Date_______________

research your event in the library using both text references and the internet.

The final projects will then be put together in chronological order on a measured timeline.

Understanding Fossil Evidence

Read pages 422 – 423 to discover how complex and challenging paleontology can be. Summarize your findings on what sorts of complications paleontologist come across when trying to reconstruct species from fossils.

Assignment: Check and Reflect, page 424, # 1 – 4. Assess Your Learning, page 425, # 1 – 10.

Science 7 – Unit E: Planet Earth Page 34 of 36

Name _________________________ Date_______________

We’ve reached the end of Unit E: Planet Earth!!!... That means your Unit exam is coming up!! Some study tips!!! Review your definitions

Review your notes and ask yourself questions Make study notes using index cards, write a question on one side of

the card and the answer on the back side (this is a great way to study with a friend)

Study with your friends (not chatting!)… by quizzing each other Review your past quizzes, especially the parts in which you

struggled with the first time! Go over your Check and Reflect and Assess your Learning Questions At the back of each Unit in the textbook are extra practice questions

that you can complete, try them!! And for goodness sake… DO NOT CRAM. You should be reviewing

your lessons each day at home; this will help you to retain your information and lessens the stress as you approach exam time!

Things to do the day of the exam! RELAX!!! Eat a good breakfast… in order for your brain to work it needs food

too!!!

Science 7 – Unit E: Planet Earth Page 35 of 36

Name _________________________ Date_______________

And most importantly… Believe in yourself! YOU CAN DO IT!!!

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