$\begin{array}{1 1} \sin \theta \sqrt{\frac{\pi \lambda gL}{\mu_0 \cos \theta}} \\ 2\sin \theta \sqrt{\frac{\pi \lambda gL}{\mu_0 \cos \theta}} \\ 2 \sqrt{\frac{\pi g L}{\mu_0}\tan \theta} \\ \sqrt{\frac{\pi \lambda gL}{\mu_0} \tan\theta} \end{array} $