Available Answers

1. 1.

   Choose and write the correct answer (MCQs):

   1. The sanitary sewage from homes is called:
      1. industrial sewage
      2. commercial sewage
      3. domestic sewage
      4. none of these 
   2. More sludge is formed at:
      1. primary stage
      2. secondary stage
      3. tertiary stage
      4. none of these
   3. The black remain in sewage treatment is used as :
      1. pesticides
      2. fertilizer
      3. insecticides
      4. none of these
2. 2.

   Write T for true or F for false:

   1. Sewage consists mainly of human excreta.
   2. Micro-organisms decompose the organic matter present in sewage.
   3. Chlorination is done to remove the foul smell of water.
   4. Suspended matter present in sewage which settles in settling.
3. 3.

   Match the column A with column B:

   A	B
   1. Sewage	a. cause of disease
   2. Contamination of drinking water with sewage	b. passing through screen
   3. First stage of sewage treatment	c. chlorination
   4. Last stage of sewage treatment	d. human excreta, soaps, other liquid wastes from kitchen and toilet.

    

4. 4.

   Write the harmful effects caused by sewage.

5. 5.

   Write some methods to stop the contamination of water.
6. 6.

   Explain the different types of waste products.