(a) Solve the equation \(2 \operatorname{cosec}^{2} \theta-5=5 \cot \theta\) for \(-180^{\circ} \leqslant \theta \leqslant 180^{\circ}\). (b) Solve the equation \(3 \sin (2 \phi+1.5)=2\) for \(0\lt \phi\lt 5\), where \(\phi\) is in radians.