$*7-20.$ Determine the resultant internal loadings acting on the cross section at point $C$ in the beam. The load $D$ has a mass of $300kg$ and is being hoisted by the motor $M$ with constant velocity.

$7-21.$ Determine the resultant internal loadings acting on the cross section at point $E.$ The load $D$ has a mass of $300kg$ and is being hoisted by the motor $M$ with constant velocity.

$7-22.$ The metal stud punch is subjected to a force of $120N$ on the handle. Determine the magnitude of the reactive force at the pin A and in the short link $BC.$ Also, determine the resultant internal loadings acting on the cross section at point $D.$

$7-23.$ Determine the resultant internal loadings acting on the cross section at point $E$ of the handle arm, and on the cross section of the short link $BC.$