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C. Match the following :

Column 'A' Column 'B'
1. Mantle (a) 2900 km
2. Minerals (b) SIMA

3. Oceanic crust (c) Materials from the rocks
4. Clay (d) Changes into state

D. Write ‘T’ for true and ‘F’ for false :
1. The earth is made up of two concentric layers.
2. The mantle, is the second layer, below the crust.
3. A rock in which a particular mineral is found in large percentage is called an ORE.
4. Igneous rocks are also called primary rocks.
5. Basalt, obsidian are the examples of extrusive igneous rocks.

E. Answer these Questions :
1. Name the different layers of the earth.
2. Give a brief account on different types of rocks.
3. Differentiate between the intrusive and extrusive igneous rocks.

4. How are sedimentary rocks formed from sediments?
5. How are the rocks and minerals are useful for human beings?
6. What do you know about the rock cycle?

Life Skills and Value (Activity)

• Prepare a list of number of objects used in your home that are made up of different minerals.
• Make a model of the earth showing the structure of its interior.

Social Studies-7-7
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