Please load theChickWeightdataset from the "datasets" package usingdata(ChickWeight). This dataset "has 578 rows and 4 columns from an experiment on the effect of diet on early growth of chicks." You will use theChickWeightdataset for the next four (4) questions.

Create a subset data frame with only those rows where Time == 21 and Diet is equal to "1" or "3." You can confirm that your subset is correct by comparing the first six (6) rows of your data frame to those below.

> head(df)

weight Time Chick Diet

12 205 21 1 1

24 215 21 2 1

36 202 21 3 1

48 157 21 4 1

60 223 21 5 1

72 157 21 6 1

Using the "weight" data, test the null hypothesis of equal mean weights for Diets "1" and "3." This should be done using the aov() function.