What is the magnitude of the net torque on the pulley about the axle?

What is the magnitude of the net torque on the pulley about the
axle?

let,
force F1=20 N
force F2=30 N
diameter of the pully d=4cm
radius of the pully r=d/2=2cm

net torque =(r*F2)-(r*F1)
=r*(F2-F1)
=0.02*(30-20)
=0.2 N.m —-is answer