Page 164 - Science Class 07

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E. Short answer ques ons.
1. How did water occur on the earth?

2. Write the importance of water in economic development.
3. How can you say that there is a scarcity of potable water on the earth?
4. Write any ﬁve ways for the conserva on of water.

5. Write the causes of water pollu on.
6. Write any eight ways for the preven on of water pollu on.
F. Long answer ques ons.
1. Explain the availability of water on the earth.

2. How can we control water pollu on?
3. Write any four steps for the conserva on of water.
4. Why rain water harves ng has become so important?

5. Write any three causes of water pollu on.
Project ActivityActivityActivity
Project
Project
Project Activity
A. Take an outline map of India and mark the regions where people are facing the problem of
water shortage. Paste the map on a chart paper and men on the main causes of water
shortage. Also, men on some methods to get rid of this problem.

B. Take a li le amount of water from diﬀerent places such as pond, river, tap, etc. and observe
it carefully with the help of microscope. Make a list of your ﬁndings.

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HO
HO
HOTSTSTS
HOTS
A. How can each of us help in making sewage treatment in our city more eﬃcient?
B. What problems can arise due to improper drainage?

C. Why do we feel the need for conserva on of water more today than our ancestors did?

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