Using a telephone survey a team of sociologists collect data

Using a telephone survey, a team of sociologists collect data on education and income for 154 individuals. Let X_i be the highest grade completed by the i^th respondent (example X_i =14 means that i^th respondent completed 2 years of college). Let y_i be the income of the i^th respondent. The sociologists have computed the following quantities after running the simple linear regression to predict the income of the individual by the highest grade completed: Report the predicted income for an individual who completed 12^th grade. Report the 95% confidence interval for the expected change in income for each additional grade completed. (make sure to report the lower then upper limit) When testing for a significant linear relationship in your regression analysis using the 95% Confidence interval for the expected change in income for each additional grade completed, which of the following is the decision and conclusion?

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