Classify each one of the following angles as right, straight, acute, obtuse or reflex:
(a)

(b)

(c)

(d)

(e)

(f)
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To do:

We have to classify the given angles as right, straight, acute, obtuse or reflex.

Solution:

(a) The given angle is less than $90^o$.

Therefore, it is an acute angle.

(b) The given angle is more than $90^o$ but less than $180^o$

Therefore, it is an obtuse angle.

(c) The given angle is equal to $90^o$

Therefore, it is a right angle.

(d) The given angle is more than $180^o$ but less than $360^o$

Therefore, it is a reflex angle.

(e) The given angle is equal to $180^o$

Therefore, it is a straight angle.

(f) The given angles are less than $90^o$.

Therefore, they are acute angles.