In each part, a point is given in rectangular coordinates. Find two pairs of polar coordinates for the point, one pair satisfying $r \geq 0$ and $0 \leq \theta<2 \pi,$ and the second pair satisfying $r \geq 0$ and $-2 \pi<\bar{\theta} \leq 0$.
(a) (-5,0)
(b) $(2 \sqrt{3},-2)$
(c) (0,-2)
(d) (-8,-8)
(e) $(-3,3 \sqrt{3})$
(f) (1,1)