500
compare the movement of the Earth around the Sun to the movement of a baseball thrown to home base. Use scientific terminology
A curveball spinning and moving toward home plate has the same rotation as the Earth rotating and revolving around the Sun.
The ball is not just spinning, but moving from the mound to home plate. The fly is able to to view the girl from now the front of the ball because of the rotation of the ball moving to the plate (much like the earth's rotation and season changes as it revolves around the Sun)