A student with a mass of $40.0 \mathrm{~kg}$ can throw a 5.00 -kg ball with a relative speed of $10.0 \mathrm{~m} / \mathrm{s}$. The student is standing at rest on a cart of mass $10.0 \mathrm{~kg}$ that can move without friction. If the student throws the ball horizontally, what will the velocity of the ball with respect to the ground be?