Aman stands at a point a on the bank of a straight river, 3 mi wide. to reach point b, l = 9 mi downstream on the opposite bank, he first rows his boat to point p on the opposite bank and then walks the remaining distance x to b, as shown in the figure. he can row at a speed of 2 mi/h and walk at a speed of 5 mi/h.

(a) find a function that models the time t needed for the trip.
(b) where should he land so that he reaches b as soon as possible? (round your answer to two decimal places.)