$\cos A =\large\frac{3}{4}$$=>32 \sin \bigg(\large\frac{A}{2}\bigg)$$ \sin \bigg(\large\frac{5A}{2}\bigg)=$

Question

\[\begin {array} {1 1} (a)\;7 & \quad (b)\;8 \\ (c)\;13 & \quad (d)\;11 \end {array}\]