The acceleration due to gravity is not due to the Earth's motion through space. It is due to the gravitational force pulling you towards the center of mass of the Earth. The ground pushes back<span>, and what you </span>feel<span> is </span>your<span> weight. This is the same as what you </span>feel<span> in an accelerating </span>car<span>.</span>
Honestly would say A not sure
The number of repetitions per second is called the frequency and is the inverse of the period. The period, T, is normally measured in seconds, and the frequency, ν, in Hertz. When the oscillations<span> (or vibrations) affect the material around them a </span>wave <span>is formed which transports energy away.</span>
Displacement of an object is equal to distance from starting point to end point.
Let's use positive numbers for movement towards east and negative numbers fro movements towards west. First movement is +50m, second movement is -30m. We add these numbers to find displacement.

Total displacement is 20m towards east.
I’m pretty sure light. But I’m not 100% sure