Two Masses Are Suspended by a Cord That Passes Over $m_{1}$

Multiple Choice

Two masses are suspended by a cord that passes over a pulley with negligible mass. The cord also has negligible mass. One of the masses, $m_{1}$ , has a mass of $7.0 \mathrm{~kg}$ and the other mass, $m_{2}$ , has a mass of $3.0 \mathrm{~kg}$ . The pulley turns on a shaft through the center of the pulley, which supports the pulley and all the masses. The vertical force of the shaft on the pulley is

A) $49 \mathrm{~N}$ downward.
B) $98 \mathrm{~N}$ upward.
C) $82 \mathrm{~N}$ upward.
D) $82 \mathrm{~N}$ downward.
E) $49 \mathrm{~N}$ upward.