At time t = 0, an object is dropped from point A that rebounds inelastically (losing some of its kinetic energy) with a speed of 10 m/s after making a collision with the ground. It finally attains the maximum possible height at t = 4 s. What is the difference of heights at t = 0 and at t = 4 s ? (Ignore air resistance as well as the time of impact)
(a) 35 m
(b) 40 m
(c) 45 m
(d) zero
