A pond has a surface area of 1.0 acre. A stream flows into the pond at a steady flow rate of 1.20cfs (cubic feet per second) for the entire year. The evaporation rate, also steady for the entire year, is 1.0 inch/month. Assume that the pond is circular and has straight sides (that is, it has the shape of a cylinder). The pond has no outflow stream but a farmer withdraws water for four months of the year at a rate of 3.50 cfs.

a. What annual change in pond volume corresponds to the evaporation rate of 1.0 inch/month? That is, what volume of water evaporates in one year?

b. What is the annual change in storage in the pond, in ft3, due to all inflows and outflows?

c. What is the change in water depth for one year?