Suppose you make a one-time deposit of P dollars into a savings account that earns interest at an annual rate of p% compounded continuously. The balance in the account after t years is B(P,r,t)=Pet, where r=p/100 (for example, if the annual interest rate is 4%, then r=0.04 ). Let the interest rate be fixed at r=0.04. a. With a target balance of $4000, find the set of all points (P,t) that satisfy B=4000. This curve gives all deposits P and times t that result in a balance of $4000. b. Repeat part (a) with B=$2500,$3000,$3500, and $4500, and draw the resulting level curves of the balance function. c. In general, on one level curve, if t increases, does P increase or decrease