Forces and equilibrium — practice question

A small smooth ring $R$ with weight $8.5\,\text{N}$ is carried by a light inextensible string passing through it. The two string ends are fixed at points $A$ and $B$, with $A$ vertically above $B$. A horizontal force of magnitude $15.5\,\text{N}$ acts on $R$, and the ring is in equilibrium with angle $ARB = 90^\circ$. The segment $AR$ of the string is inclined at angle $\theta$ to the horizontal, while $BR$ is inclined at angle $\theta$ to the vertical (see diagram). The tension in the string is $T\,\text{N}$.