If your keg is not moving the only energy your leg can have is Potential energy.
I think these gases are water vapor and nitrogen. As the temperature rises, these water vapor molecules, would condense and form the oceans we have. Also, it was said that in the early atmosphere, nitrogen is very abundant and even today the composition of air is 79% by volume.
Answer:
The force of the nail pushing in the opposite direction
False.
Theories are hypotheses that have been shown to accurately and predictably explain results obtained through repeated experimentation, to the point where the hypothesis can be assumed to be true. Then, such a hypothesis would be considered a theory.