Second Order Derivative of a Function in Use

The following graphs were used by the CEO of the Madison Savings Bank to illustrate what effect a projected promotional campaign would have on its deposits over the next year. The functions D1 and D2 give the projected amount of money on deposit with the bank over the next 12 month with and without the proposed promotional campaign, respectively. a) Determine the signs of D;(t), D;(t), Df(t) and D(t) on the interval (0.12). b] What can you conclude about the rate of change of the growth rate of the money on deposit with the bank with and without the proposed promotional campaign