Answer:
See belowStep-by-step explanation:
1. 645° = 360° + 180° + 90° + 15°
angle 645° can also be written as 360° + 180° + 90° + 15°.
This angle is in the 4th quadrant. A complete rotation is equal to 360°.
Angle is presented in the picture below:
b) 645° = 645 x π/180 = 43π/12 radians
c) Positive angle = 285°
Negative angle = -75°
d) Reference angle = 75°