A bag contains four different cards, labeled green, red, blue and yellow. Two cards are selected at random from the bag "replacement," meaning that after the first selection is made, the selected card is returned to the bag before the second selection is made. "At random" means that all cards in the box have an equal chance of being selected.
a. Define the sample space for this experiment.
Hint: how many combinations you can select two cards from four cards with four different colors. You need to clearly write down.
b. Is the event of choosing card green or blue on the first selection independent of choosing card green or red on the second selection? Why or why not?
Hint: how many times green could come first if two cards (let us say that four times) are selected or the same for blue. Think of that and then divide it by probability for entire set given in a section. You know how to find independence?