Which one of the following is responsible for causing skin cancer and mutation?</h2></div>

What causes rapid melting of glaciers?<span><br> </span></h2></div>

Which type of electron is present in free radical?</h2></div>

What causes effects of ozone layer?<span><br> </span></h2></div>

What happens in the tertiary treatment for water pollution?

<span>Name any two water pollutants which are toxic for plants and animals.</span></h2></div>

A lake receiving nutrients would be</h2></div>

What is global warming? Mention any four measures to control global warming.</h2></div>