Complementary Angles
Two angles are complementary when the sum of their measures is 90 degrees.
An angle of 90 degrees is usually marked as a small square near the vertex formed by two or more lines
Angles 3 and 4 are complementary angles because the small square is the angle that 3 and 4 are added to.
Thus, given that the measure of angle 4 is 28°, the measure of angle 3 is 90°-28° = 62°
Answer: The measure of angle 3 is 62°. Choice a