A balloon is rising vertically above a level, straight road at a constant rate of 3 ft! sec. Just when the balloon is 70 ft above the ground, a bicycle moving at a constant rate of 11 ft/ sec passes under it. How fast is the distance s(t) between the bicycle and balloon increasing 6 seconds later? 3' s(t) L _'_.K D xiii s(t) is increasing by 9' ft/ sec. (Simplify your answer.)