Beam $PQRS$ has internal hinges in spans $PQ$ and $RS$ as shown. The beam may be subjected to a moving distributed vertical load of maximum intensity $4 \:kN/m$ of any length anywhere on the beam. The maximum absolute value of the shear force (in $kN$) that can occur due to this loading just to the right of support $Q$ shall be
- $30$
- $40$
- $45$
- $55$