A steel pipe fittings company claims that the yield strength of its nontempered couplings is more variable than that of its tempered couplings. A random sample of nine tempered couplings has a standard deviation of 13.1 megapascals, and a similar sample of nine nontempered couplings has a standard deviation of 25.4 megapascals. From past data, it is known that company's production process results in normally distributed yield strengths. Test the company's claim at a = 0.05.