3 Load the package MASS and attach(birthwt) 1. Look at the help file on the birthwt data and note how many rows and columns the dataset contains. 2. Find the maximum age of a mother in the birthwt data. 3. What is the smallest birthwt in grams? 4. Execute the command plot(lwt,bwt) and include it in your document. Problem 4 1. What is the R code needed to create a matrix that looks like [1,] [2,] [3,] [4,] [,1] [,2] [,3] [,4] 1 5 9 13 2 6 10 14 3 7 11 15 4 8 12 16 Store this matrix in m. 2. Create a vector called d that contains the diagonal entries of m. 3. Create a new matrix called x that is the same as m but has 0 along the diagonal. Problem 5 You keep track of your commute times from home to the John and 6th Street parking garage on campus for several days and have the following data in minutes: 14 17 11 13 15 15 16 19 12 1. Save these in a vector called commute. 2. Evaluate: length(commute). 3. Evaluate: commute>12 4. Evaluate: sum(commute>12) 5. Evaluate: commute[commute>12] 2