Midpoint between (6,9) (0,1)

What is the size of the matrix resulting from

Joe has some money in his bank account he deposits 45$ write an expression that represents the amount of money in joe's account

For the chance to be team captain, the numbers 1-30 are put in a hat and you get two chances to pick a number, without replacement. which formula correctly shows how to find the probability that you choose the number 1 and then 2?