In a test of military ordnance, a large number of bombs were dropped on a target from various heights. The initial velocity of the bombs in the direction of the ground was 0. Let y be the height in meters from which a bomb is dropped, let x be the time in seconds for the bomb to strike the ground, let w = x2, and let v = y√ . The relationship between x and y is given by y = 4.9x2. For which of the following pairs of variables is the correlation coefficient is an appropriate summary. Check all that apply.

x and y

w and y

x and v

w and v

ln x and ln y