[填空题]
The forearm in Fig. 8–45 ac3c01*:en auh w6ithxe 64c ivccelerates a 3.6-kg ball c .wq+atr + fi/p ea ibcmh-6(a(jr7h4at 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