What is the problem in this article? what solution does the article propose? (site 1)

The energy of a photon was found to be 3.38 × 10–19 j. planck’s constant is 6.63 × 10–34 j • s. which color of light corresponds to this photon?

An athlete is holding 24 lb of weights at a height of 6 inches above the stack as shown. to lower the weights, she applies a constant force of 5 lb to the handle. determine the velocity of the weights immediately before they hit the stack.

Aball is thrown horizontally from a cliff at 8m/s .in what direction is the ball moving 2s later?