Answer
(a) See the graph.
(b) Quadrant II
(c) $\frac{2\pi}{3}$ and $-\frac{10\pi}{3}$
Work Step by Step
(b) A positive coterminal angle of $-\frac{4\pi}{3}$ is $\frac{2\pi}{3}$
$\frac{\pi}{2}\lt\frac{2\pi}{3}\lt\pi$, therefore, it lies in quadrant II.
(c)
$-\frac{4\pi}{3}+2\pi=\frac{2\pi}{3}$
$-\frac{4\pi}{3}-2\pi=-\frac{10\pi}{3}$
