[填空题]
A person exerts a force of 55 N on the end of a 0nc;cx.uq+oq. 8 .7hdawizfcmok:*j door 74 cm wide. What is g85yzlz,0 d10xc;1 t ljajt zuthe magnitude of the torque if the force is ext8zt1j5 1yzlulxa ; j gdz0,c0erted (a) perpendicular to the door $m \cdot N$ (b) at a 45 $^{\circ} $ angle to the face of the door? $m \cdot N$