In Drosophila, singed bristles (sn)and cut wings (ct)are both caused by recessive, X-linked alleles.The wild-type alleles (sn+
)are responsible for straight bristles and intact wings, respectively.A female homozygous for sn and ct+
is crossed to a sn+ct
flies are interbred.The F2
males are distributed as follows:
What is the map distance between sn and ct?