The amount of simple interest accrued on a sum of money varies jointly with the amount of money, the interest rate, and the time the money is invested. a sum of money is invested at 4% for 3 years and accrues $168 in interest. the same sum of money is invested in a second account at 6% for 4 years. which statement is true?

a. the amount of interest accrued on the second account is less than double the amount of interest accrued on the first account.
b. the amount of interest accrued on the second account is double the amount of interest accrued on the first account.
c. the amount of interest accrued on the second account is more than double but less than triple the interest on the first account.
d. the amount of interest accrued on the second account is more than triple the interest accrued on the first account.