93. Online Banking. In 2000, about 39.4 million
American households conducted at least some of
their banking online. By 2010, that number had
risen to about 72.5 million. Let N(t) represent the
number of American households using online
banking, in millions, t years after 2000.
a) Find a linear function that fits the data.
b) Use the function of part (a) to predict the num-
ber of American households that will use online
banking in 2015.
c) In what year will 157 million American house-
holds use online banking?