please I need help in solving this problems

1. Examine the textbook data set "payroll.csv". Identify the variables and give their types. 2. Nathan, Kelsey, Cindy, Brad, Amy and Maggie want to play a game. This game has three players per team. They wish for the teams to be randomly assigned. List all possible samples (without replacement) of size 3. (a) What is the chance of Nathan, Brad and Amy being on the same team? (b) What is the chance of Kelsey, Cindy and Amy being on the same team? (c) What is the chance that any three players (Nathan, Kelsey, Cindy, Brad, Amy or Maggie) will be on the same team? Modern Mathematical Statistics with Applications, Devore, J. and Berk, K., Thomson (2007), Chapter 2 3. The "mammals" data set is a built-in dataset in the "MASS" library of R. The "mammals" data set contains the result of a study of sleep in mammal species. First, load the "mammals" data set into your R workspace. In Rstudio, you can click on the "Packages" tab and then on the checkbox next to MASS. Without Rstudio, type the following command in R console: data(mammals,package="MASS") A random experiment is to choose one of the species listed in this data set. All outcomes are equally likely. You can obtain a list of the species in the event "brain > 500" with the command subset(mammals,brain>500) What is the probability of this event, i.e., what is the probability that you randomly select a species with a brain weight greater than 500g? Hint: you can obtain a count of the species with brain weights greater than 500g, by sum(mammals$brain>500)