Question#$1$ Solve the following problem involving exponential growth of bacteria colonies.

Suppose that the concentration of a bacteria sample is$100,000$ bacteria per milliliter. If the concentration doubles every $3$hours$,$ how long will it take for the concentration to reach $350,000$ bacteria per$$ milliliter?

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Part $1$

It will take about enter your response here $$hour$($s$)$ for the concentration to reach $350,000$ bacteria per milliliter.

$($Do not round until the final answer. Then round to the nearest tenth as$$ needed.$)$ Question#$2-$ Use the appropriate amortization formula to find $($a$)$ the monthly $($n$=12)$ payment on a loan with the given conditions and $($b$)$ the total interest that will be paid during the term of the loan.

$$11,300$ is amortized over $7$ years at an interest rate of $11\mathrm{.}4\%.$

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Part $1$

$($a$)$ The monthly payment is $$$enter your response here.

$($Round to the nearest$$ cent.$)$

Part $2$

$($b$)$ The total interest paid is $$$enter your response here.

$($Round to the nearest$$ cent.$)$ Question#$3-$ As age$$ increases, so does the likelihood of a particular disease. The fraction of people x years old with the disease is modeled by f$($x$)=$

$0\mathrm{.}8$

$1+273$e$0\mathrm{.}122$x$.$

$($a$)$ Evaluate $$f$(35)$ and $$f$(60).$ Interpret the results.

$($b$)$ At what age does this likelihood equal $60\%?$

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Part $1$

$($a$)$ Select the correct choice below and fill in the answer boxes within your choice.

A$.$

$$f$(35)$enter your response here and f$(60)$enter your response here $($Round to three decimal places as$$ needed.$)$

This means that among people age enter your response here$,35\%$ have the$$ disease, while among people age enter your response here$,60\%$ have the disease.

B$.$

$$f$(35)$enter your response here and f$(60)$enter your response here $($Round to three decimal places as$$ needed.$)$

This means that among people age $35,$ enter your response here$\%$ have the$$ disease, while among people age $60,$ enter your response here$\%$ have the disease.

Part $2$

$($b$)$ At about enter your response here yr this likelihood equals $60\%.$

$($Do not round until the final answer. Then round to the nearest integer as$$ needed.$)$