What will be the environmental consequence of a $25\%$ increase of $CO_2$ level in our atmosphere?

Greenhouse effect is primarily due to the presence of:

Global warming can be controlled by

Consider the following statements and select the correct set with respect to global warming:
$(a)$ $El$ $Nino$ effect
$(b)$ Cooling of stratosphere and earth surface
$(c)$ Shifting of climatic zones
$(d)$ Snow blindness
$(e)$ Impairment of hearing
$(f)$ Excessive deposition of ice at poles
$(g)$ Rise in sea level
$(h)$ Increase in eutrophication

Choose the correct option for the proportion of various greenhouse gases contributing to global warming.

If there is no greenhouse effect,the average temperature at the surface of the Earth would have been: (in $^{\circ} C$)