torque exerted on the drum

Question

The force$F_{1}$  and$F_{2}$ in a brake band and the direction of rotation of the drum are as shown in the
figure. The coefficient of friction is 0.25. The angle of wrap is 3$\pi$/2 radians. It is given that “R = 1
m and $F_{2}$ = 1N. The torque (in N-m) exerted on the drum is ___________