You are modelling sales for your firm as a function of advertising expenditures and years. What is the correct interpretation for Year (holding all else constant)? Linear Regression: Sales Estimate Standard Error P (Intercept) 323.54 177.60 1.82 _118 Advertising 13.99 10.22 1.37 .220 Year 46.60 50.03 0.93 388 for each additional year, sales increase by over 46 units for each additional year, sales decrease by over 46 units O for the average year, sales increase by over 46 units for an additional 10 years, sales increases by over 46 units sales have not changed over year when controlling for expenditures on advertising