Problem #$1(2$ pts$)$: Brooke just bought sets of solar panels to power the ventilation and heating in

four of her $2000f{t}^2$ greenhouses. The panels cost $$18,000$ today and will reduce her electricity bills

by average of $$400$ per month $($average of four seasons$).$ How long will it take her to recoup her

investment in the panels if she can earn $12\%$ interest, compounded monthly, on her money? $($Hint:

You can use either the Series Present Worth Factor formula, or you can use linear interpolation!$)$

Problem # $2(2$ pts$)$: Your company has a $$800,000.$ loan for a new plasma soldering machine.

The interest rate for this loan is $5\%$ per year and your company's initial plan is to pay for the loan

in exactly $15$ years. Annual payment is made at the end of each year.

$($a$)$ What is the Annual Payment your company has to pay at the end of each year?

$($b$)$ Based on the initial annual payment calculated above, your company has now decides

that it can afford to pay $$100,000$ per year, which is more than the initial annual payment.

By paying $$100,000$ annually, how many payments $($years$)$ will the loan of $$800,000.$ be paid

off? Assuming the same interest rate is used, i$.$e$.5\%$ annually.

$($c$)$ By paying $$100,000$ annually, how much is the last payment?