Answer:
always runs slower than normal.
Explanation:
The basic concept of theory of relativity was given famous scientist, Albert Einstein. The relativity theory provides the theory of space and time, which are the two aspects of spacetime.
According to the theory of relativity, the laws of physics are same for all the non-accelerating observers.
In the context, according to the theory of relativity, a moving clock relative tot a stationary observer always runs slower than the normal time.
To solve this problem we will apply the linear motion kinematic equations, which describe the change in velocity, depending on the acceleration and the distance traveled, that is,

Where,
= Final Velocity
= Initial Velocity
a = Acceleration
h = height
Our values are given as,

Replacing we have,



Therefore the height of the cliff is 121ft
E, there is no state of matter that has no particle motion, however a solid's particles are only vibrating.