Consider the beam, supported with a hinge at A and C and a rolier at B$.$ It is loaded with a point load of $40kN$ applied between A and B$,$ and point load of $20kN$ applied between B and C as shown. El is constant. Determine the final moments of member CB $($at joint $MC{B}_{CB})$ in $kN-m.$

a$.41\mathrm{.}25$

b$.-18\mathrm{.}07$

c$.67\mathrm{.}75$

d$.0$