Here's a three-part puzzler. For each part list the sample space. Listing the sample space will make the probability clear. You can denote Boy as B, Girl as G, and Florida as F when listing a sample space. For example, the sample space of the birth events boy-girl and girl-girl is {BG, GG}.

a) Your friend has two children. What is the probability that both are girls? b) Your friend has two children. You know for a fact that at least one of them is a girl. What is the probability that the other one is a girl? c) Your friend has three children. One is a girl named Florida and one is a girl named Holley. What is the probability that the first child is a boy?