2. A collar moves on a shaft under the action of force F. Force F remains horizontal throughout the motion of the collar. Determine an expression for the velocity of the collar as it reaches position B if it starts from rest at position A. Friction may be neglected.

any one of the statements could be an accurate comparison. but the statement that would define the correct choice and seal the deal is not even on the list:

"the visibilities of vector-x and vector-y in the drawing provided with the question are identical and nonexistent."

photocells convert light energy to electricity

i believe the answer would be:

d. violin, clarinet, french horn, and tuba