$\"\"$

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(a)

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Total amount $\"\"$ .

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The rate of interest is $\"\"$

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Since the amount is doubled, $\"\"$ .

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Formula for continuous compounding is $\"\"$

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Substitute $\"\"$ and $\"\"$ in above equation.

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$\"\"$

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Apply logarithm on each side.

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$\"\"$

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Use the formula: $\"\"$

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$\"\"$

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The time required for the amount to double is $\"\"$ sec.

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$\"\"$

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(b)

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Since the amount is tripled, $\"\"$ .

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Formula for continuous compounding is $\"\"$

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Substitute $\"\"$ and $\"\"$ in above equation.

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$\"\"$

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Apply logarithm on each side.

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$\"\"$

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Use the formula: $\"\"$

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$\"\"$

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The time required for the amount to triple is $\"\"$ sec. $\"\"$

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(a) The time required for the amount to double is $\"\"$ sec.

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(b) The time required for the amount to triple is $\"\"$ sec.