5 A block of weight 100 N is on a rough plane that is inclined at \(35 ^ { \circ }\) to the horizontal. The block is in equilibrium with a horizontal force of 40 N acting on it, as shown in Fig. 5.
\begin{figure}[h]
\includegraphics[alt={},max width=\textwidth]{3be85526-3872-42ac-8278-1d4a3cf75ff7-4_490_874_379_591}
\captionsetup{labelformat=empty}
\caption{Fig. 5}
\end{figure}
Calculate the frictional force acting on the block.