Assume the average selling price for houses in a certain county is $351,000 with a standard deviation of $41,000. a) Determine the coefficient of variation. b) Caculate the z-score for a house that sells for $377,000. c) Using the Empirical Rule, determine the range of prices that includes 68% of the homes around the mean. + a) Determine the coefficient of variation. CV=% (Round to one decimal place as needed.) b) Calculate the z-score for a house that sells for $377,000. Z= (Round to two decimal places as needed.) c) Using the Empirical Rule, determine the range of prices that includes 68% of the homes around the mean. upper bound x = $ lower bound x= $ (Round to the nearest dollar as needed.)