- Determine 2 positive and 2 negative co-terminal angles for a related acute angle of 20° in quadrant III.
- Using the CAST rule, state the sign of each of the following:

- sin 220°
- cos 320°
- tan 112°
- Determine θ if cos θ = 1/2 and θ is an angle in quadrant IV.
- The CAST Rule describes for a quadrant which ratios have positive values. Describe why the tangent ratio is positive only in quadrants I and III.
- Given a point on the x-y plane, explain how you would determine a principal angle that would correspond to a terminal arm containing that point.