Answer:
30°
Step-by-step explanation:
The protractor in the picture is positioned correctly - YAY!!
Since we want the measure of ∠BCA, we'll look at the angle from side CB (this is the 0° side) up to side CA. Side CA goes through the numbers 30 and 150, but 150 is based on going backward from 180°, not forward from 0°.
