The beam shown below has a distributed load $(P=4\frac{N}{m})$ acting on a portion of it$.$ A concentrated force $F=8N$ is applied to point $C($ where $c=3,d=4,e=5).$ Point $D$ is just to the left of roller support $B$ which has a clockwise couple moment of $M=12Nm$ applied on it $($i$.$e$.$ couple moment is acting at B $).$ If a $=3m,b=1\mathrm{.}5m,$ determine the internal normal force, shear force, and moment at points D and E $.$ Note that the support at point A is a pin.