Kinetic energy ___ as speed ___

In 2002, the rare earth elements mine in mountain pass, california was closed because

The twister and runaway train are two coasters at the same amusement park. both coasters start at the same height. the coaster for the twister is twice the mass of the coaster for the runaway train. which roller coaster has greater gravitational potential energy at the start of the ride?

If two objects at different te,peraure are in contact with each other what happens to their temperature