$3-45$

R$1$:$10000$

R$2$:$5000$

a:$12\mathrm{.}5$

Mb:$-30000$

Mx:$31250$

a$.$

Solve for max shear stress due to V

B$.$

Shear stress from the max magnitude bending stress

C$.$shear stress at the transition point at B