The Nobb Door Company manufactures doors for recreational vehicles. It has two conflicting objectives: It wants to build doors as small as possible to save on material costs, but to preserve its good reputation with the public, it feels obligated to manufacture doors that are tall enough for 95 percent of the adult population in the United States to pass through without stooping. In order to determine the height at which to manufacture doors, Nobb is willing to assume that the height of adults in America is normally distributed with mean 73 inches and standard deviation 6 inches. How tall should Nobb's doors be?