Step 1:

(a)

The sector of a circle center angle is $\"\"$ . \ \ Radius is $\"\"$ . \ \

Find the area of a sector of a circle.

General formula for the area of a sector of a circle is

$\"\"$ \ \

Substitute angle is $\"\"$ and radius is $\"\"$ in the above formula. \ \

$\"\"$

The area of a sector of a circle is $\"\"$

Second choice is right answer.

(b)

The sector of a circle center angle is $\"\"$ . \ \ Radius is $\"\"$ . \ \

Substitute angle is $\"\"$ and radius is $\"\"$ in the area of a sector of a circle formula. \ \

$\"\"$

The area of a sector of a circle is $\"\"$

Solution:

(a)

The area of a sector of a circle measures angle $\"\"$ and radius $\"\"$ is $\"\"$

(b)

The area of a sector of a circle measures angle $\"\"$ and radius $\"\"$ is $\"\"$