Available Answers

1. 1.

   Choose the correct answer.

   1. The coldest layer of atmosphere is
      1. troposphere
      2. stratosphere
      3. mesosphere
      4. exosphere
   2. In the process of purification of water chlorine tablets are added to
      1. kill the germs in water
      2. remove the soluble impurities from the water
      3. remove the insoluble impurities from the water
      4. remove the suspended impurities from the water
   3. The soil is formed by the process of
      1. fossilisation
      2. weathering of rocks
      3. atmosphere of moon
      4. rock cycle
   4. Tides are caused due to the
      1. gravity of moon
      2. mass of moon
      3. atmosphere of moon
      4. craters of moon
   5. A light rock with lots of holes in it is
      1. marble
      2. sandstone
      3. pumice
      4. slate
2. 2.

   Which rock is used to make blackboard and slates?
3. 3.

   What is meant by tsunami?
4. 4.

   Name the main greenhouse gas.
5. 5.

   Why are eclipses occur?
6. 6.

   What is carrying away of top soil by wind or water called?