companies aggressively compete for credit card holders. The percentage of Americans having credit cards ha in recent years, as shown in the following table. Year Percentage of Americans Having a Credit Card 1989 1992 1995 1998 2001 Percentage 62.4 66.4 67.5 72.7 (a) Use these data to determine the linear least squares regression function with percentage having a credit card as function of years since 1989 (x = 0 for 1989). (Round any numerical values to two decimal places.) 56.0 (b) Use the linear function to estimate the percentage having a credit card in 1980. (Round your answer to one decimal place.) 9 Use the linear function to estimate the percentage having a credit card in 2004. (Round your answer to one decimal place) (d) According to the function, when will 100% of Americans have a credit card? (Round your answer to the nearest year.) View Previous Question Question 10 of 20 View Next Question My aiment esc