Forces and equilibrium — practice question

The diagram illustrates a smooth ring $R$, of mass $m\,\text{kg}$, threaded onto a light inextensible string. A horizontal force with magnitude $2\,\text{N}$ acts on $R$. The two ends of the string are fixed at points $A$ and $B$ on a vertical wall. The section $AR$ of the string is at an angle of $30^\circ$ to the vertical, the section $BR$ is at an angle of $40^\circ$ to the vertical, and the string is taut. The ring is in equilibrium.