Sarah and Thomas are thinking about having kids. They are concerned that because Thomas’s father was diagnosed with cystic fibrosis last year, it could run in the family. Cystic fibrosis is a recessive genetic disorder which affects the respiratory system. Both Thomas and Sarah get tested for the recessive allele (f), with the results indicating that they are each carriers of the disorder (a genotype of Ff). Is it possible for Sarah and Thomas to develop cystic fibrosis? Explain. (2)