Saphy

The allele b gives Drosophila flies a black body and b + gives brown, the wild-type phenotype. The allele wx of a separate gene gives waxy wings and wx + gives nonwaxy, the wild-type phenotype. The allele cn of a third gene gives cinnabar eyes and cn + gives red, the wild-type phenotype. A female heterozygous for these three genes is testcrossed, and 1000 progeny are classified as follows: 5 wild type 6 black, waxy, cinnabar 69 waxy, cinnabar 67 black 382 cinnabar 379 black, waxy 48 waxy 44 black, cinnabar a. Explain these numbers for each progeny class in terms of genetic linkage. b. Draw the alleles in their proper positions on the chromosomes of the triple heterozygote female used in the above testcross. c. If it is appropriate according to your explanation, calculate interference. d. If two triple heterozygotes of the type in this problem are crossed, what proportion of progeny would be black, waxy? (Remember, there is no crossing-over in Drosophila males.) (I understand a. & b. but not c. and d; feel free to provide an approach. thank you)