Answer
$$
M_C=22.5 \mathrm{~N} \cdot \mathrm{m}↻
$$
Work Step by Step
$$
\begin{aligned}
& ↺+M_c=\Sigma M ; \quad M_c=-75(0.15+0.15) \\
& =-22.5 \mathrm{~N} \cdot \mathrm{m}=22.5 \mathrm{~N} \cdot \mathrm{m} \text { ↻ } \\
&
\end{aligned}
$$