Q$15)$ A cantilever $2\mathrm{.}5$ m long is loaded with a uniformly distributed load of $10$ kN$/$m over a length of $1\mathrm{.}5$ m from the fixed end. Determine the slope at the free end of the cantilever. Take flexural rigidity of the beam as $1\mathrm{.}9*10^12$ N$-$mm$2$