<span>A wedge is a double sided screw basically. Therefore, the difference is the number of sides.</span>
Radiation is a type of heat transfer wherein there is no need for medium or media through which the heat will flow. Consequently, the radiation waves are able to travel through vacuum. The best observation as evidence to conclude that heat is indeed transferred by radiation is the increase of temperature of the receiving body.
Answer:
Greatest gravitational energy is at "C".
The planet has to do work "against" the field to get to "C".
Also, if m v R (angular momentum) is constant then as R increases v must decrease for this term to be constant and KE = 1/2 M v^2 must decrease also to get to point C.
There are no true statements at all on the list of choices
that you included with the question.