$\"\"$

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Area of a sector of a circle is $\"\"$ .

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Central angle of a circle is $\"\"$ .

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Area of the sector : $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in $\"\"$ .

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$\"\"$

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Radius of the circle is $\"\"$ m. $\"\"$

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Radius of the circle is $\"\"$ m.