World climate is threatened by increase in the concentration of</h2></div>

What are biomedical wastes?</h2></div>

A successful forest conservation strategy should involve</h2></div>

Name two international efforts to check ozone depletion</h2></div>

Ozone-layer is getting depleted because of</h2></div>

When domestic sewage mixes with river water </h2></div>

Ozone layer is disturbed by</h2></div>

Main cause of extinction of species from tropical areas is</h2></div>