Notice that all eight of the angles in the center of the pattern meet to form a circle. Let a° represent the measure of each pink central angle and b° represent the measure of each green central angle. Which of the following equations are true? Select all that apply. 4a° = 180° 2b° = 90° 4a° + 4b° = 360° a° = 90° - b° 2(a° + b°) = 180°