An experiment was conducted to compare soybean yields of plo

An experiment was conducted to compare soybean yields of plots treated with one of three herbicides (A, B, or C) or a control (D). A total of 32 soybean plots were used in the experiment; 8 plots were randomly assigned to each of the four treatments. Statistics summarizing the yields in bushels per acre are provided in the following table. Specify the coefficients on the linear combination of means to measure each of the following: You do not need to estimate the linear combination. The effect of herbicide A on soybean yield. The average effect of herbicide treatment on soybean yield. If the average of the three herbicide yield means is larger than 60 bushels per acre. For each of the scenarios in (2a) explain why the linear combination is, or is not, a contrast. Construct a 95% confidence interval for the average of the three herbicide means minus the control mean. Show all your work.

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