Calculate the momentum of electron moving with $\large\frac{1}{3}$rd velocity of light

Question

$\begin{array}{1 1}(a)\;9.69\times 10^{-18}gcm/s&(b)\;9.89\times 10^{-11}gcm/s\\(c)\;8.32\times 10^{-18}gcm/s&(d)\;8.98\times 10^{-11}gcm/s\end{array}$