Participating in physical activity can to reduce stress in all of the following ways except:
a. it releases stored energy
b. it causes fatigue and exhaustion
c. it releases tension
d. it relaxes muscles

Arailroad car collides with and sticks to an identical railroad car that is initially at rest. after the collision, the total kinetic energy of the two cars is a) the same as before. b) half as much as before. c) one third as much as before. d) one fourth as much as before. e) twice as much as before.