The reference angle after rotating the unit circle anti-clockwise is; π/3 Radians
<h3>How to draw a Unit Circle?</h3>
To draw the angle θ = -120° in the unit circle, we will move clockwise 90°, and thereafter another angle of 30°.
This tells us that we pass the fourth quadrant and stop in the third quadrant.
The reference angle of an angle theta in the third quadrant, is; θ + 180°.
Thus, the reference angle of -120° is; -120° + 180° = 60°.
Converting 60° to radians gives; (60/360) * 2π Radians = π/3 Radians
Thus, the Reference angle is π/3 Radians
Read more about Unit Circle at; brainly.com/question/20691579
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