A phenotypically normal woman is known to have the X-chromosome constitution gd +/+ hemA. The recessive allele gd is associated with a deficiency of the enzyme glucose 6-phosphate dehydrogenase in the red blood cells, and hemA is the recessive allele determining classical hemophilia. If the genetic distance between the two loci is 16 cM, what is the probability that a son born to this woman will be phenotypically normal with respect to both of these traits? Explain. (this question has to do with gene mapping second year genetics)