Give one protective function of forest.

Water is a valuable resource. List two ways that you would suggest every family member to save this resource.

According to the $2010$ report,how many total National Parks are there in India?

$(a)$ Locate and name the water reservoirs in Figures $(a)$ and $(b)$.
$(b)$ Which has an advantage over the other and why?

What does the high level of total coliform count in river Ganga indicate?

The $pH$ of a water sample collected from a river was found to be acidic in the range of $3.5-4.5$. On the banks of the river were several factories that were discharging effluents into the river. The effluents of which one of the following factories is the most likely cause for lowering the $pH$ of river water?