Two identical spanners are used to loosen identical nuts. In case I, a 20N force is applied at 0.20m making 90∘ with the spanner. In case II, a 30N force is applied at 0.15m making 60∘ with the spanner. In case III, a 25N force is applied at 0.25m making 30∘ with the spanner. Which case produces the greatest torque?
a) Case II
b) Case I
c) All three produce equal torque
d) Case III