A spherical water balloon is being filled with water so that its radius after t seconds is 8t/t+2 inches. After t seconds,

(a) . . . how quickly is the radius changing? (That is, what is the instantaneous rate of change of the radius with respect to time?)

(b) . . . how much water is inside the balloon?

(c) . . . how quickly is the amount of water changing? (Is it increasing or decreasing?) Please include units with the solutions