A simply supported beam is subjected ti a uniformly distributed load of intensity $w$ per unit length, on half of the span from one end. The length of the span and the flexural stiffness are denoted as $l$ and $EI$, respectively. The deflection at mid-span of the beam is

1. $\dfrac{5}{6144} \dfrac{wl^4}{EI} \\$
2. $\dfrac{5}{768} \dfrac{wl^4}{EI} \\$
3. $\dfrac{5}{384} \dfrac{wl^4}{EI} \\$
4. $\dfrac{5}{192} \dfrac{wl^4}{EI}$