25. If a sum of $1000 is deposited into an account that pays r% interest compounded semiannually, the balance after 12 years is given by r 24 . dA _ A _ 1000(1 +) .Findgwhenr _ 6.5. 26. Suppose that the profit (in hundreds of dollars} from selling x units of a product is given by 2 P(x) = (x1)2 number of units sold 1: =4. (Hint: Use quotient rule} . Find the marginal profit when the 27. An average student enrolled in a typing class div 5 _ progressed at a rate of f = 69 0'\" words per minute 1: weeks after enrolling in a 15-week course. If a student could type 25 words per minute at the beginning of the course, how many words per minute N(t) would the student he expected to type 1'. weeks into the course? After completing the course. 28. Given the price-supply function p = 5(x) = 8020-05" 1) find the average price (in dollars} over the supply interval [45, 50]