Answer
$0.290N.m$
Work Step by Step
We can find the magnitude of the frictional torque as follows:
$\Sigma \tau=-r(m_1g)+r(m_2g)=0$
$\implies \tau_{fr}=rg(m_1-m_2)$
We plug in the known values to obtain:
$\tau=(0.0940)(9.81)(0.635-0.321)$
$\tau=0.290N.m$