If the function $g(x) = \left\{ \begin{array} {1 1} k \sqrt {x+1}, & \quad 0 \leq x 3 \\ mx=2 ,& \quad 3 < x \leq 5 \end{array} \right.$ is differential, then the value of $k+m$ is :

Question

$\begin{array}{1 1} 2 \\ \frac{16}{5} \\ \frac{10}{3} \\ 4 \end{array}$