A statistician, who loves taking care of his sports car, wondered if there was a relationship between the number of car washes a car owner gets for his car each year and the amount of repair costs he has to pay each year. The statistician collected data from a random sample of 25 car owners, and the results are summarized below. Mean Standard Deviation x = number of car washes 6.7200 3.8893 y = repair costs $967.72 $413.54 correlation = -0.7039 a) What is the equation of the least squares regression line? (2 decimal places) y where x = number of car washes per year and y = predicted repair costs per year (In dollars) b) What percent of the variability in repair costs is explained by the linear relationship between number of car washes and repair costs? (enter your answer as a percent, rounded to two decimal places, without the percent sign, for example 12.34)