[填空题]
A person exerts a forp37v qf otui2)ce8dggsr eu4k8. v w2ed4 ah9:, 1jhxsys of 55 N on the end of a door 74 cm wide. What is the magnitude of the torque if the force is exert:, gh481 saheu4sr98ey 2jsdkxw.vgded (a) perpendicular to the door $m \cdot N$ (b) at a 45 $^{\circ} $ angle to the face of the door? $m \cdot N$