In order to study the effect of fertilizers, five groups of 1-acre plots were randomly selected. One group was not treated with any fertilizers and the remaining four groups were treated with four different brands of fertilizers. Table 12.19 gives the yields of corn (in bushels) from each of these plots.
Use the data to determine whether there is a difference in yields for different fertilizers. Use α = 0.01.
Table 12.19 Yield by Fertilizer

273641 None: Fertilize 69 Fertilizer II Fertilizer 102 111 Fertilizer IV: 127 115 112 122 114 107 116 112 108 506975 36 18 996 58 27 48 67 57 63 49 65 95 89 100 92 103 102 94 100 112 114 9479 693