Problem 4 An experiment performed on flies examined the effect of two food sources on the lengths of their eye stalks. The data is in the file "fly_eye_stalk.csv". One group was fed corn, and an independent group was fed cotton. Estimate the size of the effect of interest here. Perform and report on the results of an appropriate statistical test for comparing the mean eye stalk length in the two groups. Include diagnostic plots to check your assumptions and justify your choice of test. (You may use any R function in your solution.) #