A cyclist rides one lap of a circular track at a constant speed so that the riders distance, d meters, from the starting point at any time, t seconds, after starting is: d= (50) - ( 50cos x (pi)t/30, find:

(a) the time taken to complete one lap
(b) the radius of the track
(c) the maximum distance from the start
(d) the length of the track
(e) the distance of the cyclist from the starting point at (i) 15 seconds (ii) 40 seconds
(f) the time (nearest second) at which the cyclist is 93n3 m from the starting point