"A balloon is rising vertically above a level, straight road at a constant rate of 4 ft/sec. Just when the balloon is 56 feet above the ground, a bicycle moving at a constant rate of 17 ft/sec passes under it.

a) How fast is the distance s(t) between the bicycle and the balloon increasing 3 seconds later?

b) How fast is the angle between y(t) and s(t) changing at that time?"