Determine the frequency of revolution of the electron in $2^{nd}$ Bohr's orbit in hydrogen atom

Question

$\begin{array}{1 1}(a)\;9.3\times 10^{15}Hz&(b)\;8.28\times 10^{16}Hz\\(c)\;7.32\times 10^{16}Hz&(d)\;8.13\times 10^{16}Hz\end{array}$