Question 7 (2 points) An investigation into whether more expensive cell phone batteries last longer included a linear regression analysis of the battery duration (measured in hours) as explained by the cost of the battery (in dollars) for 20 randomly selected cell phones. The partial output from the linear regression analysis is displayed below: Standard Coefficients Error Intercept 19.627 13.651 Cost 4.172 3.197 Use this output to conduct the following: Calculate a 95% confidence interval for the true population slope and provide an appropriate interpretation. Based solely on this interval, do you believe there is evidence of a linear relationship between battery cost and duration? Justify your response. NOTE: You do not need to show your calculations of the confidence interval. Just state your final interval to four decimal places