Test the validity of the equal-variance assumption in problem 8-61. If you reject the null hypothesis of equal-population variance, redo the test of problem 8-61 using another method.

In problem The power of supercomputers derives from the idea of parallel processing. Engineers at Cray Research are interested in determining whether one of two parallel processing designs produces faster average computing time, or whether the two designs are equally fast. The following are the results, in seconds, of independent random computation times using the two designs.

Design 1 Design 2 2.6, 2.5, 2.0, 2.1, 2.6, 3.0, 2.0, 1.7, 2.3, 2.8, 1.9, 3.0, 2.5, 1.8, 2.2 2.3, 2.0, 2.4, 2.8, 3.1, 2.7 2.6