Select the letter of the correct answer. Based on the article, which best replaces the question mark in the diagram above?

If you were to drop a rock from a tall building, assuming that it had not yet hit the ground, and neglecting air resistance. what is its vertical displacement (in m) after 6 s?

Which of the following changes will result in a stronger electromagnet? a. using fewer coils of wire b. using a higher voltage c. using a shorter nail d. using a longer wire

You are given a vector a = 125i and an unknown vector b that is perpendicular to a. the cross-product of these two vectors is a × b = 98k. what is the y-component of vector b?