[填空题]
A 55-kg person riding a bike puts all her weight on aiit45rk bb*ag okl. 1aqf-u mp )*2b8each pedal when climbing a e3yxf,r;yid (hill. The pedalsi x(yfy ;r3de, rotate in a circle of radius 17 cm. (a) What is the maximum torque she exerts? $m \cdot N$ (b) How could she exert more torque?