In this problem you will do some hypothesis testing on a built-in R dataset. The dataset is PlantGrowth, and it contains samples of weights of harvests from fields that have undergone different treatments ("ctrl", "trt1", "trt2"). The question you will examine is whether each treatment improves plant yields compared to the control. You will assume that the variances of the different groups are the same (but unknown) and you want to set your critical value for type I error rate of 5%. Use R to generate the critical value for this experiment with a 95% confidence. Show your code (paste)