Find 12 so that stress distribution is in equilibrium with zero body force and so that the traction vector on the plane x1=1.

a. Calculate 5t.
b. Discuss if the flow is laminar or turbulent (based on Re and the velocity profile).
c. Replace the loading by an equivalent resultant force and couple moment acting at point O.
d. Determine the displacement of end a with respect to end b when the joint is subjected to the axial loads shown.