7.)(1 point) A couple plans to have three children. There are 8 possible arrangements of girls and boys. For example, GGB means the first two children are girls and the third child is a boy. All 8 arrangements are (approximately) equally likely.

(a) Write down all 8 arrangements of the sexes of three children in a list separated by commas.

(b) What is the probability of any one of these arrangements above?

(c) Let X be the number of girls the couple has. What is the probability that X = 2?

9.)(1 point) Let Y be a random number between 0 and 1 produced by the uniform distribution as discussed in idealized random number generator described in Figures 10.4 and 10.5 and Example 10.8 of the 6th edition of Moore, Notz and Fligner. Find the following probabilities:

(a)P(Y0.6)P(Y0.6)

(b)P(Y<0.6)P(Y<0.6)

(c)P(0.6Y0.7)