Zuhaib is anxiously waiting for the results of his calculus test and is pacing back and forth as shown in the graph below. 

1. At which point $(a, b, c, \text{ or } d)$ is Zuhaib’s speed the greatest? Approximate the rate.

   Hint 1(a):

   This is a distance/position graph. Notice how Zuhaib is moving forward and backwards as she paces.

   Hint 2(a):

   Speed is the absolute value of velocity. And velocity is the slope of a distance graph.

   Hint 3(a):

   At which point is the absolute value of the slope the steepest?

2. At which point is Zuhaib’s velocity the greatest? Approximate the rate.

   Hint (b):

   Velocity is the slope on a distance/position graph.

3. What is the difference between speed and velocity?

   Hint (c):

   Speed is the absolute value of velocity.