Draw a unit circle. In which quadrants is sine negative?

1. What special reference angle is this value related to?
2. In which quadrants is cosine positive?

$\tan(\theta)=\frac{\sin(\theta)}{\cos(\theta)}$ 

$\tan(\theta)=\frac{\sqrt{3}}{1}=\frac{\sqrt{3}/2}{1/2}$ 

Since sine is related to the $y$-value of the coordinates of the unit circle, where on the unit circle is $y=−1$?