A uniform rigid beam with length $3.2\,\text{m}$ is supported on a pivot at its midpoint. As illustrated, two children are positioned at opposite ends of the beam. One child has mass $24\,\text{kg}$, while the other has mass $36\,\text{kg}$. Because the heavier child makes one end of the beam rest permanently on the ground, the beam is inclined at an angle of $20^{\circ}$ to the horizontal ground. Calculate the moment of the weight of the $24\,\text{kg}$ child about the pivot.
- A$72\,\text{N m}$
- B$130\,\text{N m}$
- C$350\,\text{N m}$
- D$380\,\text{N m}$