C.) Apple offers a buyback program for iPhones after they are 5 years old. They offer to buy your phone for $100. Would this be a profitable decision to sell your
phone back to Apille after 5 years? Explain your reasoning. PLEASE HELP AND WRITE IT OUT PLS

It would not be profitable to sell it back for 100$.

Step-by-step explanation:

It would not be profitable because you might have payed 300-1000$ (Depending what phone you buy) for your phone. It would only be profitable for the older generation of the phones like iPhone 5 and iPhone 6.

Ok so Jessica bought M pens, which cost $6.70 each.
She also bought 4 fewer pencils than pens, or (M-4) pencils, at $3.50 each.

So in total, she spent:
6.7M + 3.5(M-4)
= 6.7M + 3.5M - 14
= 10.2M -14

So she spent $(10M - 14) on pens and pencils.

Hope this helped