Why is the formation of sand a physical change

Choose all the answers that apply. our solar system: is in a spiral galaxy no longer includes pluto is made mostly of empty space is in the andromeda galaxy is the only known system that supports life

This is important 1. what happens to the speed of molecules in water vapor when it condenses to form a liquid? (2 points) the molecules slow down. the molecules speed up. the molecules slow down and then speed up. the molecules speed up and then slow down. 2. how might human activities change to compensate for a decrease in water supplies? (2 points) humans might build a factory. humans might build drainage systems. humans might extract more water from the ground. human behavior does not change because of the water cycle. i'll be grateful if anyone can answer these 2 questions !

If we relied solely on the nonrenewable resources found in the u.s., which one would we run out of first at current usage levels? a. natural gas b. oil c. uranium d. coal