[Total: 9 points] One of the great discoveries of biology is that organisms have a class of genes called "regulatory genes," whose only job is to regulate the activity of other genes. How many genes does the typical regulatory gene regulate? A study of interaction networks in yeast (S. cerevesiae) came up with the following data for 109 regulatory genes (Guelzim et al. 2002). Demonstrate how to calculate this problem in R coding based upon the dataset given below, then please answer the following question:

1) What is the estimated mean number of genes regulated by a regulatory gene in the yeast genome? Use R coding to calculate this. (Hint: Using the mutate function in tutorial 5. [2 points,1 point for calculation, show which formula used, and 1 point for R coding]