Consider a simple population consisting of only the numbers $1,2,$ and 3 (an unlimited number of each). There are nine different samples of size 2 that could be drawn from this population: (1,1),(1,2),(1,3),(2,1),(2,2),(2,3) (3,1),(3,2),(3,3)
a. If the population consists of the numbers $1,2,3,$ and 4, list all the samples of size 2 that could possibly be selected.
b. If the population consists of the numbers $1,2,$ and 3 list all the samples of size 3 that could possibly be selected.