How is the air at the surface of the Earth heated? A. The air is heated by the sun.

B. The air is heated as solar energy is transferred to the equator and then dispersed to the two hemispheres.

C. The air is heated by the transfer of thermal energy from the ground below.

If the speed of a particle triples ,by what factor does its kinetic energy increase?

Curious carl calculated the density of a cube to be 4.50 g/cm3. what is the density of the cube in g/l?

In the sport of parasailing, a person is attached to a rope being pulled by a boat while hanging from a parachute-like sail. a rider is towed at a constant speed by a rope that is at an angle of 15 ∘ from horizontal. the tension in the rope is 1900 n. the force of the sail on the rider is 30∘ from horizontal. what is the weight of the rider? express your answer with the appropriate units.