A person is in a small boat in the pointAon one side of a lake parallel shores. He will move fromAto pointBon the lake's other side as shown. The total time for transfer is assumed to beys. He paddles 3 m/s and run 5 m/s.

a) expressyas a function ofx(see figure).

b) examine graphically whether he can cope with the movement in 2 min.

c) determination by differentiation the shortest time to transfer.