What are the effects of Noise pollution?

Which of the following substances is responsible for causing fluorosis?

1. Lead
2. Fluorides
3. Arsenic
4. Mercury

Which of the following processes is responsible for the depletion of oxygen from the water body?

1. Biomagnification
2. Bioaccumulatiom
3. Eutrophication
4. Oxygen cycle

Bhopal Gas Tragedy(3rd December,1984) was caused by the release of

1. CFC
2. Nitrogen dioxide
3. Sulphur dioxide
4. MIC