Answer: The measure of the angle indicated in the figure could be - 180° (Option a.)
Solution:
1. If we measure the angle in counterclockwise the sign is positive, then the angle could be:
180°, 180°+360°=540°, 180°+2(360°)=180°+720°=900°, ...
1. If we measure the angle in clockwise the sign is negative, then the angle could be:
-180°, -180°-360°=-540°, -180°-2(360°)=-180°-720°=-900°,...
Then, of the given options, the measure of the angle indicated in the figure could be -180° (option a.)