A machinist squeezes the handle of visegrip pliers while loosening a frozen bolt (Figure...

A machinist squeezes the handle of visegrip pliers while loosening a frozen bolt (Figure P5.31). The connection at point A, which is shown in a magnified cross-sectional view, supports a 4.1-kN force.

(a) Determine the shear stress in the 6-mm-diameter rivet at A.

(b) Determine the factor of safety against yielding if the rivet is formed from 4340 steel alloy.