Problem $7$: Water flows in a branched pipe system with given directions as seen in Figure. Water flows velocity is $12\frac{m}{s}$ in pipe $(2)$ which is opened to the atm at the end of the pipe. Velocity is $9\frac{m}{s}$ for pipe $3.$

a$)$ Find the magnitude and direction of the flow force on the junction section.

b$)$ Calculate the normal and shear stress for on pipe $(1).$ Find the bending moment at $1m$ behind the junction point for this pipe. $($Y$$ksel$,2016).$