A balloon is rising vertically above a level, straight road at a constant rate of 2 ft divided by sec. Just when the balloon is 84 ft above the ground, a bicycle moving at a constant rate of 12 ft divided by sec passes under it. How fast is the distance s (t )between the bicycle and balloon increasing 6 seconds later? A coordinate plane has a horizontal x-axis and a vertical y-axis. The angle between the axes is marked with a small square. The location of a balloon on the vertical axis is labeled y(t). An arrow pointing upward lies on the y-axis just below the point y(t). The location of a bicycle on the horizontal axis is labeled x(t). An arrow pointing to the right lies on the x-axis to the right of the point x(t). A segment falling from left to right begins at the balloon and ends at the bicycle and is labeled s(t).