A. describe what happens to the molecules of water as water goes from ice to liquid to vapor
b. explain what happens to the temperature during and between these phase changes

A.)When heated, the molecules get loser, and the dipole dipole interaction is still there, but they dont stay so closely together, and jossle around with momentary meetings of opposite charges 
B.The heat is used to break the bonds between the ice molecules as they turn into a liquid phase. 

W= fd
where f is an applied force and d is the distance over which it is applied. when a parachuting skydiver is at constant velocity, he is experiencing "terminal velocity", the point at which his acceleration down is canceled out by air resistance. that means that the resisting force of the air is equal to his weight, but in the opposite direction. with this, we can solve for the work done by the force.
w = fd
w = (92.0)(9.81 m/s^2) (325)
w= 2.93 x 10^5 j
the value for work in this case is positive because it is pushing up on the skydiver, who has a downward force of gravity.
therefore the answer is 2.93 x 10^5 j

One answer could be erosion