Answer
$ a). 2.9325 Nm$
$b). 58.65N$
Work Step by Step
a). Torque = $I \times $ angular acceleration
=$0.55\times4.55=2.5025Nm$
$T_{applied} = T_{f} + 2.5025=0.43+2.5025Nm=2.9325Nm$
b). $F=\frac{T_{applied}}{r}=\frac{2.9325}{0.05}=58.65N$