With this question I got
$\cos\alpha=-\sqrt{3}$ and $-r\sin\alpha=1$
thus $r\sin\alpha=-1$. Both of these are negative, so my solution should be in third quadrant. In the answer however, it is in first quadrant and I don't understand why. I got $\alpha= 210^\circ$ but the answer is $\alpha=30^\circ$.