The yield of a chemical process expressed in percentage of the theoretical maximum is measured with each of two catalyst a and b and with no catalyst(control c). five observation are made under each condition making the usual assumption for an analysis of variance test the hypothesis that there is no difference in main yield between the three condition. use the 5% level of significance a(79.2,80.1,77.4,77.6,77.8). b(81.5,80.7,80.5,81.7,80.6). c(74.8,76.5,74.7,74.8,74.9).