Exactly 2 years ago, Lauren deposited $1,000 in a local bank at 8 percent interest. At the end of the first year, she earned $80 interest, and she immediately reinvested that amount. At the end of the second year, Lauren earned $86.40 interest on her $1,080 amount at the bank. What is the extra $6.40 that Lauren earned in interest during the second year called? Group of answer choices simple interest interest on interest dividend income