8.2.9. Agronomists have identied 7 different geographical areas with respect to raising corn in West Virginia and have managed to obtain an experimental farm in each area. To see if a single variety of corn can be recommended for the entire state, the two leading varieties are compared for yield at all 7 localities. The following yields in bushels per acre are obtained: Geographical Area Variety 1 2 3 4 5 6 7 A 45 41 58 60 42 32 57 B 47 44 62 63 46 35 59 (a A) 2 3 4 3 4 3 2 (34)2 4 9 16 9 16 9 4 Why is it a good design to compare the two varieties at each location? What is the average difference in the yields? Show that the estimated standard error of this difference is 0.309. mpg. . The seed company that sells variety B claims it will exceed variety A in yield by more than 2 bushels per acre. Test this claim at a: = 0.05. e. What is your conclusion about the seed company's claim? f. Find a 95% central condence interval on the mean difference in yield of the two types of seed. How is this condence interval related to the test in part d