Find how many more cars carl expects to sell over the next

Question

Question: EFFECT OF TV ADVERTISING ON CAR SALES Carl Williams, the proprietor of Carl Williams Auto Sales, estimates that with extensive television advertising, car sales over the next several years could be increasing at the rate of

5e^0.3t

Thousand cars/year, t yr from now, instead of at the current rate of

(5 + 0.5t^3/2)

Thousand cars/year, t yr from now. Find how many more cars Carl expects to sell over the next 5 yr by implementing his advertising plans.