please help. people take my points without answering. 15 points left, please show work. and please dont just take my points

Step-by-step explanation:

Reference angle in quadrant I,

θ' = θ

Reference angle in quadrant II,

θ' = 180° - θ

Reference angle in quadrant III,

θ' = θ - 180°

Reference angle in quadrant IV,

θ' = 360° - θ

13). θ = 315°

Since, the given angle is in the 4th quadrant,

Reference angle θ' = 360° - 315°

                                 = 45°

14). θ' = (620° - 540°)

         = 80°

Reference angle = 80°

15). θ' = 630° - θ

          = 630° - 580°

          = 50°

Reference angle = 50°

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