Answer
a. point B
b. point D
c. point A, point C, point E
d. point B
Work Step by Step
a. At point B, the slope is not zero but it is less steep, so the object is moving the slowest at point B.
b. At point D, the slope is the steepest, so the object is moving the fastest at point D.
c. At points A, C, and E, the slope is zero. Therefore the object is at rest at these three points.
d. The slope is negative at point B, so the object is moving to the left at point B.