A car starting from rest accelerates at the rate f through a distance , then continues at constant speed for time t and then decelerates at the rate f/2 to come to rest. If the total distance traversed is 15 , then
(1) *=ft
(2) * = 1/6 ft2
(3) * = 1/2 ft2
(4) * = 1/4 ft2
