Available Answers

1. 1.

   Multiple choice questions:

   1. Which of the following is a natural cause of soil erosion?
      1. wind
      2. running water
      3. heavy rain
      4. all of these
   2. The traces of animals and plants in the layers of sedimentary rocks are called:
      1. lava
      2. fossils
      3. fossil fuels
      4. none of these
   3. Impure water contains many disease causing germs like those of:
      1. cholera
      2. jaundice
      3. dysentery
      4. all of these
   4. Plants and trees hold the soil by their:
      1. roots
      2. stems
      3. leaves
      4. seeds
2. 2.

   Fill in the blanks:

   1. __________________ is added in water to kill germs.
   2. Rocks are divided into _________________ groups.
   3. Air exerts ____________________ in all directions.
   4. ______________________ is a metamorphic shale.
   5. Air contaains _______________ % nitrogen and _______________ % oxygen.
3. 3.

   Why do we feel uncomfortable on a humid day?
4. 4.

   Name the various layers of the atmosphere.
5. 5.

   What are fossils?