Convert from polar to rectangular coordinates:

$\mathbf{(a)}\quad(3,\frac{3\pi}{2})\quad\Rightarrow_{(x,y)}\quad$(,)

$\mathbf{(b)}\quad(6,\frac{\pi}{6})\quad\Rightarrow_{(x,y)}\quad$(,)

$\mathbf{(c)}\quad(3,\frac{\pi}{3})\quad\Rightarrow_{(x,y)}\quad$(,)