(a) It is an acute angle as its measure is less than 90°

(b) It is an obtuse angle because its measure is more than 90° but less than 180°

(c) Right angle as its measure is 90°

(d) Reflex angle as its measure is more than 180° but less 360°

(e) Straight angle as its measure is 180°

(f) Acute angle as its measure is less than 90°.