The finite sequence whose general term is an = 0.17n2 - 1.02n + 6.67 where n = 1, 2, 3, ..., 9 models the total operating costs, in millions of dollars, for a company from 1991 through 1999. find
a. $21.58 million
b. $27.4 million
c. $23.28 million
d. $29.1 million