The graph below shows the total distance , in miles, traveled by
a bicyclist after hours.

(a) Estimate the bicyclist's average velocity over the
following time intervals.
Over , the average velocity is approximately mi/hr.
Over , the average velocity is approximately mi/hr.
Over , the average velocity is approximately mi/hr.

(b) Estimate the bicyclist's instantaneous velocity at the following times.
At hour, the instantaneous velocity is approximately mi/hr.
At hours, the instantaneous velocity is approximately mi/hr.
At hours, the instantaneous velocity is approximately mi/hr.

(c) Estimate the bicyclist's maximum velocity and the specific time at which it occurs.
The maximum velocity is approximately mi/hr, which occurs when hr.