5) Suppose you are trying to relate the price of a house to several of its characteristics. You propose the following regression model: price - Bo + Bisqrft + B2bdrms + u. Here, price is the house price in dollars, sqift is the total area of the house in square feet, and barms is the number of bedrooms in the house. a) (4 points) Explain the conditions under which estimating this relationship by OLS would produce and unbiased estimate of B1 b) (4 points) Suppose you decide that the lot size matters for determining the price of a house, so you add it to the regression model to get price - Bo + Bisqrft + B2bdrms + B; lotsize + u. Here lotsize is the total area of the land on which the house is built. Would the adjusted R2 in this regression be higher or lower than the one without lot size? Explain. c) (4 points) Suppose you discover that all of the houses in the sample are on the same size lot. What problem, if any, would this cause for estimating this relationship using OLS