[填空题]
The forearm in Fig. 8–45 accd63k-cbr bu3w/q7 u -o mq4fwaelerates a 3.6-kg0lq;p obm6 whu8q) qf+edd 5(j ball at 7 $m/s^2$ by means of the triceps muscle, as shown. Calculate (a) the torque needed, $m \cdot N$ (b) the force that must be exerted by the triceps muscle. Ignore the mass of the arm. N