Bullet and ball

You're standing on the edge of an ocean with a high powered rifle and a ball. The ocean is smooth and there is no wind. Holding the rifle level with the ground six feet high, you fire a bullet out to sea. The very instant the bullet leaves the barrel you drop the ball from the same height as the rifle. Which will hit the water first, the bullet or the ball?

Answer: The ball will hit first. The curvature of the earth will cause the bullet to travel farther down, even though they both drop at the same rate of speed.