Representation of data — practice question

A particle $P$ with mass $0.15\,\text{kg}$ is fastened to one end of a light elastic string whose natural length is $0.4\,\text{m}$ and whose modulus of elasticity is $12\,\text{N}$. The opposite end of the string is fixed at point $A$. Particle $P$ moves in a horizontal circle centred vertically beneath $A$, with the string making an angle of $\theta^\circ$ to the vertical and $AP = 0.5\,\text{m}$.