Leslie$$ Mosallam, who recently sold her$$ Porsche, placed $$$$9,600$ in a savings account paying annual compound interest of $4$ percent.

a$.$Calculate the amount of money that will accumulate if Leslie leaves the money in the bank for $3,7,$ and $17$year$($s$).$

b$.$Suppose Leslie moves her money into an account that pays $6$ percent or one that pays $8$ percent. Rework part $($a$)$ using $6$ percent and $8$ percent.

c$.$What conclusions can you draw about the relationship between interest$$ rates, time, and future sums from the calculations you just$$ did?