A curve has parametric equations
\(x=2 \sin 2 t, \quad y=3 \cos 2 t,\)
for \(0\lt t\lt \frac{1}{2} \pi\). For the point on the curve where \(t=\frac{1}{3} \pi\), find the value of
(i) \(\frac{\mathrm{d} y}{\mathrm{~d} x}\),
(ii) \(\frac{\mathrm{d}^{2} y}{\mathrm{~d} x^{2}}\).