“Black Friday,” the Friday after Thanksgiving, is traditionally the beginning of the Christmas shopping season, and is the busiest shopping day of the year. An economist believes there is a...

“Black Friday,” the Friday after Thanksgiving, is traditionally the beginning of the Christmas shopping season, and is the busiest shopping day of the year. An economist believes there is a relationship between the time of day at which a consumer starts shopping on Black Friday and the amount of money spent that day. Suppose a random sample of Black Friday shoppers was obtained and the shopping start time (x, in hours after 6:00 a.m.) and the total amount spent ( y, in hundreds of dollars) was recorded for each. SHOPPER

a. Find the estimated regression line, and complete the ANOVA table.

b. Describe the relationship between shopping start time and total amount spent on Black Friday. What would you recommend to retailers to increase business?

c. Find a 95% prediction interval for an observed value of shopping start time of 8:00 a.m.

d. Suppose the shopping start time is 9:00 a.m. Is there any evidence to suggest that the true mean amount spent is greater than $725? Use a significance level of 0.05.