Is a deceasing linear model or an exponential decay model likely to be a better fit for the data about remembering? ?

The table shows the balance of a money market account over time. write a function that represents the balance y(in dollars) after t years.

Each month, a shopkeeper spends 5x + 14 dollars on rent and electricity. if he spends 3x−5 dollars on rent, how much does he spend on electricity? for which value(s) of x is the amount the shopkeeper spends on electricity less than $100? explain how you found the value(s).

What multiplys to be 1 but adds up to be 4