A roller coaster needs more kinetic energy to reach the top of a tall Hill what are two ways that the engineer can increase the amount of kinetic energy the roller coaster has

What component of earth’s atmosphere exists entirely as a result of photosynthesis?

The energy equivalent of the rest mass of an electron is

Aprisoner is forced to go into one of three rooms, but he can choose which room. the first room is ablaze with fire. the second one is rigged with explosives that will go off as soon as he enters. the third contains a pair of lions who haven't eaten in years. which room should he choose to survive?