Answer:
"A pendulum swinging back and forth" is an example of harmonic motion
X = Xo cos ω t
Explains the back and forth motion of the pendulum
D. March because it is just below the 1 million marker on the graph and it is the only one that low.
The marbles that are 'more energetic' fall out of the tray, in the same way particles have enough energy to escape and turn into a gas.
I think its A let me know its wrong or not