42. A study examined the relationship between population growth and change in unemployment rate in a sample of 100 U.S. cities. Based on the collected data, the least squares regression line is Unemployment = 5.21 + 11.28 Population Growth. Assume all regression conditions are met and x and y are linearly related. Which interval should we use to estimate the change in unemployment rate for a city that has an annual population growth rate of 2%?
Group of answer choices
a)A confidence interval for the slope of the regression line
b)A confidence interval for the y-intercept of the regression line
c)A prediction interval for the change in unemployment rate for a city with an annual population growth rate of 2%
d)A confidence interval for the mean change in unemployment rate for all cities with an annual population growth rate of 2%
