The work-energy principle states that an increase in the kinetic energy of a rigid body is caused by an equal amount of positive work done on the body by the resultant force acting on that body. Conversely, a decrease in kinetic energy is caused by an equal amount of negative work done by the resultant force.
Your answer would be D.
If an object has mass, it has gravity, and the more mass it has, the stronger its gravity. During the formation of planets, essentially, various matter and elements pulled and fused together (because of the gravity), forming planetesimals.
It transfers energy through the source of the sound. Your ear detects sound waves when vibrating air particles cause your ear drum to vibrate
I don't think so as long as you make it apparent that the information comes the same source. So citing over and over again is unnecessary as long as it's clear that the information is from the same website or source. If you can't make it clear that they are from the same website source, it would a safe choice to continue to cite to avoid allegations of plagiarism.