An article in the Dallas Morning News discussed the market for green cars-hybrid gasoline and electric cars, electric cars, and diesel cars. One factor the article mentioned as affecting the market for green cars was the increasing gas mileage of conventional gasoline-powered cars. How would this factor be likely to affect the price elasticity of demand for green cars? Source: Terry Box and Troy Oxford, "Green Cars Still a Small Part of New-Car Sales," Dallas Morning News, May 26, 2013.