$($Related to Checkpoint $5\mathrm{.}2)($Future value$)$ Leslie Mosallam, who recently sold her Porsche, placed $$8,400$ in a savings account paying annual

compound interest of $6$ percent.

a$.$ Calculate the amount of money that will accumulate if Leslie leaves the money in the bank for $2,6,$ and $16$ year$($s$).$

b$.$ Suppose Leslie moves her money into an account that pays $8$ percent or one that pays $10$ percent. Rework part $($a$)$ using $8$ percent and $10$

percent.

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

a$.$ After placing $$8,400$ in a savings account paying annual compound interest of $6$ percent, the amount of money that will accumulate if Leslie

leaves the money in the bank for $2$ year$($s$)$ is $$.($Round to the nearest cent.$)$