$\"\"$

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a.

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If a principal $\"\"$ is invested at an annual interest rate $\"\"$ compounded $\"\"$ times a year, then the balance $\"\"$ in the account after $\"\"$ years is given by $\"\"$ .

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Let $\"\"$ , $\"\"$ and $\"\"$ .

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$\"\"$

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Therefore, the function $\"\"$ is an exponential function.

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Regardless of the values that we substitute, the coefficient and the base of the exponent $\"\"$ will be fixed while the exponent( $\"\"$ ) will be variable since the time $\"\"$ can vary.

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$\"\"$

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b.

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Consider $\"\"$ .

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Substitute $\"\"$ , $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$

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c.

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Consider $\"\"$ .

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Substitute $\"\"$ in above function.

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$\"\"$

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Therefore, the account balance after 20 years $\"\"$ .

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$\"\"$

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a.

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The function $\"\"$ is an exponential function.

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The coefficient and the base of the exponent $\"\"$ will be fixed while the exponent( $\"\"$ ) will be variable since the time $\"\"$ can vary.

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b. $\"\"$ .

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c. The account balance after 20 years $\"\"$ .

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