You are the sales manager for a large condominium development in Florida. From the 150 condos you have build, you took a random sample of 21 units. The average sales price of these 21 condos is 350,000 with a standard deviation of 20,000. The appropriate statistical table value to apply for the 95% confidence interval for the average sales price of condos is... a) 2.074 b) 1.725 c) 1.96 d) 2.086