12. For laboratory studies of an organism, it is important to provide a medium in which the organism ourishes. The data for this exercise shown in Table 6.38 are from a completely randomized design with four samples for each of seven media. The response is the diameters of the colonies of fungus. Table 6.38 Data for Exercise 12 Medium Fungus Colony Diameters WA 4.5 4.1 4.4 4.0 RDA 7.1 6.8 7.2 6.9 PDA 7.8 7.9 7.6 7.6 6.5 6.2 6.0 6.4 5.1 5.0 5.4 5.2 6.1 6.2 6.2 6.0 7.0 6.8 6.6 6.8 (a) Perform an analysis of variance to determine whether there are different growth rates among the media