PROBLEM $9\mathrm{.}19$

For the beam and loading shown, $($a$)$ determine the equation to

find the reaction at the roller support, $($b$)$ determine the reaction

at B if L $=1$m$,$ M$0=4$ kN$-$m$,$ E $=200$ GPa, I $=2\mathrm{.}5$E$4$ mm$4$