Let me do the first half.
15: A. Because the diagonal is longer than both the other forces. Thus, it is the hypotenuse. And, the forces are all 90 degress from each other. It is like the end of a box.
17: D. There is no acceleration, so no change in kinetic energy and there for D.
22: A. Solid and liquids have the same densities and the same molecular spacing. The answer is not b, because that would imply that solids have a desnity 1000 times greater than liquids.
28: B. Increasing wavelength means that the chances of interaction decreases, and thus they are further apart.
Nid can do the rest. g2g