Suppose that 13% of all milk cartons have 1% milkfat, and 28% of all milk cartons have 2% milkfat, and 18% of all milk cartons are fat-free, and 41% of all milk cartons are of some other type. Randomly choose a carton of milk, and let X be "1" if the carton of milk is 1% milkfat, or "2" if the carton of milk is 2% milkfat, or "3" if the carton of milk is fat-free, or "4" otherwise.
a. What is the mass of X?
b. Make a plot of the probability mass function.
c. What is the CDF of X?
d. Make a plot of the CDF.