12. What kind of angle is ZH if it measures 90°? A. acute B. obtuse C. right D. reflex 13. Which statement describes a right angle? A. A right angle is an angle whose measure is 90°. B. A right angle is an angle whose measure is 180º. C. A right angle is an angle whose measure is greater than 0° but less than 90°. D. A right angle is an angle whose measure is greater than 90° but less than 180°