Section 2.1 contains the following instruction "Try creating a vector of numbers, like this:" So I typed c(5, 9, 11) and got an error message. They meant

Section 2.1 contains the following instruction "Try creating a vector of numbers, like this:" So I typed c(5, 9, 11) and got an error message. They meant "Type the R code to create this vector:" I shall work through the rest in a few days, nice environment.