Height of the tallest hill, I guess is the answer. There could be some other factors in the shape of the course like twists or spirals which would have some angular effect on the speed, as well.
Gravity and Friction
liquid
yes; wherever the coaster touches the tracks there is static friction pressing against it and it pressing against the tracks, thus keeping it from flying off.
Upside down.
It provides undesired slowing of the coaster on its path but it is essential for the brakes to stop it at the station.
Thermal energy is heat. Heat is associated with motion (like a roller coaster) because of friction. Friction slows down the speed of an object and changes some of its kinetic energy into heat.
10
a roller coaster that's made from wood of course duhhhhhhh..... sike naw im just kidding a wooden roller coaster conducts more heat than a steel roller coaster because it has more rough edges and that creates more friction and that makes heat. o a wooden roller coaster conductes more heat than a steel roller coaster does.
Of course they didn't, its clearly done with computer special effects.
Friction, slows the roller coaster down to a slow enough pace that it eventually stops.
Kinetic Energy.
Kinetic or centrifugal, depening what phase you are on.