A hockey puck slides along the ice. There is a frictional force between the ice and puck, and this is the only horizontal force on the puck. Which of the following must be true?
A. The puck will slow down and eventually come to rest.
B. The puck will continue to move at constant velocity.
C. The puck will speed up.
D. The frictional force points in a direction opposite that of the puck’s motion.
E. Both (a) and (d) are true