A Web site monitors the number of unique customer visits, producing a total for each day. The following table summarizes the totals by day of the week, averaged over the last 12 weeks. (For example,...

A Web site monitors the number of unique customer visits, producing a total for each day. The following table summarizes the totals by day of the week, averaged over the last 12 weeks. (For example, during this 12-week period, the site averaged 2,350 visitors on Mondays.)

A regression model regressed the number of visits on six dummy variables, representing the days Monday through Saturday (omitting Sunday).

(a) What is the estimated intercept
 in the regression?

(b) What is the slope of the dummy variable that represents Monday?

(c) Are the differences among the days statistically significant?