$\"\"$

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The area of the circle is $\"\"$ .

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

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$\"\"$ (Substitute 615 for A and 3.14 for $\"\"$ )

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$\"\"$ (Divide each side by 3.14)

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$\"\"$ (Cancel common terms) $\"\"$

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$\"\"$ (Divide: $\"\"$ )

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$\"\"$ (Take square root of each side)

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$\"\"$ (Cancel square and root)

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$\"\"$ (Use a calculator to find root)

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$\"\"$ (Rounded to nearest whole number) $\"\"$

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The diameter of a circle is twice to its radius, $\"\"$ .

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$\"\"$ (Multiply: $\"\"$ )

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$\"\"$

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$\"\"$

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The radius and diameter of the circle are 14 cm and 28 cm respectively.