A deck of cards has 52 cards. There are 4 suits, diamonds, hearts, clubs and spades. Each suit has 13 cards. What is the probability that I will randomly pick a 2, put it back, then randomly pick a 4?

Margie is practicing for an upcoming tennis tournament. her first serve is good 20 out of 30 times on average. margie wants to know the estimated probability that her first serve will be good at least four of the next six times she serves. how could she design a simulation for this scenario?