Arock is held under water in a pond and is dropped from rest. while it sinks to the bottom of the pond, what happens to its motion? (more than one may be correct, so choose as many as are correct.)

select one or more:
a. the acceleration decreases.
b. the velocity increases and then decreases.
c. the velocity decreases and then increases.
d. the velocity of the rock decreases until it reaches terminal velocity.
e. the friction on the rock decreases as it approaches terminal velocity.
f. the acceleration of the rock in the water depends on its weight.
g. none of the above.