According to CPCB, what particulate size is most harmful to humans:
1. more than 10 micrometers
2. between 5 to 10 micrometers
3. between 2.5 and 5 micrometers
4. less than 2.5 micrometers

Brown air consists of:

Photochemical smog is formed in traffic congested cities where the conditions are:

1. cool and intense solar radiation            

2. cool and less solar radiation

3. warm and intense solar radiation         

4. warm and less solar radiation

Photochemical smog does not contain:
1. Ozone
2. NOx
3. PAN
4. Carbon monoxide

Which of the following is not an ill effect of PAN?
1. inhibition of electron transport system in plants
2. damage to chloroplasts in plants
3. acute irritation of eyes in humans
4. leukemia in humans

The pH of normal rainwater is:

The most effective device to remove particulate matter from polluted air is:
1. electrostatic precipitator

2. cyclonic separator

3. trajectory separator

4. scrubber

The device, normally used to remove gaseous pollutants from polluted air but can remove large particulate matter as well, is:
1. electrostatic precipitator

2. cyclonic separator

3. trajectory separator

4. Scrubber

Catalytic Converters:

1. only I & II are correct
2. only I & III are correct
3. Only II & III are correct
4. I, II & III are correct

A water body has low DO content. An organism that is likely to flourish here will be:
1. Gonyaulax, an annelid
2. Gonyaulax, a nematode
3. Tubifex, an annelid
4. Tubifex, a nematode