Answer
Torque = (force)(lever arm). A longer lever arm means more torque.
At the 75-cm mark, the torque is $\frac{75 cm}{50 cm}$ = 1.5 times as much as it was originally.
At the 100-cm mark, the torque is $\frac{100 cm}{50 cm}$ = 2 times as much as it was originally.
