A square shop sign with uniform density has a mass of $2.4\,\text{kg}$ and side length $0.86\,\text{m}$. It is held up by a hinge fixed along its top edge. Because there is friction in the hinge, the sign hangs in equilibrium at an angle of $15^{\circ}$ to the vertical, as shown. Calculate the moment about the hinge due to the sign’s weight.
- A$2.6\,\text{N m}$
- B$4.0\,\text{N m}$
- C$5.2\,\text{N m}$
- D$9.8\,\text{N m}$