Answer with explanation:
Presume that, initial water level to be, 0 mm, at a time t=0.
And water level is rising at the rate of .
After 6.2 years level of water will be =1.8 × 6.2
=11.16 mm
→Averge, that is increase in water level after 6.2 years is given by
→→Rate of Depreciating of water level is given by = Negative of Increase of water level=