[填空题]
The forearm in Fig. 8–45 accelerategana43rw6 .ibze ke2 usj7j2.s a 3.6-kg t8*uoceo en9s++e(m o(u jeo;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