A random variable X has the Probability Distribution : X 1 2 3 4 P(X) $2k^2$ $k$ $k$ $k^2$ The value of k is :

$\frac{1}{3}$ $\frac{1}{5}$ $\frac{1}{2}$ $\frac{1}{6}$

$\frac{1}{3}$