C is the answer because contact force, is the only force mentioned that opposes the motion of the rock
Answer:
period = 0.833 s
frequency=1.2 Hz
Explanation:
The period is the duration of time taken for a 1 heartbeat
Frequency is the number of heartbeats per second
Answer:
Saturn is mainly composed of the lightest two gases known, hydrogen and helium. It is the only planet in our solar system whose density is less than water.
Explanation: