[填空题]
The forearm in Fig. 8ow3anfv6l 5vn m au+tzt4 /m++–45 accelerates a 3.6-kcr3a3k4 dq/1s -uquvp:.jg c rg 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