Herbicide and corn hybrids. Genetic engineering has produced new corn hybrids that resist the effects of herbicides. This allows more effective control of weeds, because herbicides don't damage the corn. A study compared the effects of the herbicide glusofinate on a number of corn hybrids. The percents of necrosis (leaf burn) 10 days after application of glusofinate for several application rates (kilograms per hectare) and three corn hybrids, two resistant and one not, are provided in the data file.13
(a) Construct a plot of means to examine the effects of application rate and hybrid and their interaction. (b) Are the conditions for ANOVA inference satisfied? Explain.