Hired you to analyze demand in 25 regional markets for a new product y, called angelica pickles. a statistical analysis of the demand in these markets shows (standard errors in parentheses): q = 250 - 10p + 6px + 0.25a + 0.04i (100) (3) (2) (0.1) (0.15) r2 = 90% standard error of the estimate = 75 here, qy is the market demand for product y, p is the price of y in dollars, a is dollars of advertising expenditures, px is the average price in dollars of another (unidentified) product, and i is dollars of household income. in a typical market, the price of y is $1,500, px is $500, advertising expenditures are $50,000, and disposable income per household is $45,000. the numbers in parentheses are standard errors of the coefficients. based on this information, do the following: a. calculate the expected level of demand for y. b. indicate the range within which actual demand is expected to fall with 95% confidence. c. interpret r2. d. test the significance of advertising (a), at α = 0.05.