A cross between individuals with genotypes a+a b+b x aa bb produces the following progeny (this…

A cross between individuals with genotypes a+a
b+b x aa bb produces the following progeny (this is a
symbolization system that is often used in microorganisms and
Drosophila: where instead of
Aand athey use
a+and
a):

a+a
b+b           83
a+a
bb            21
aa
b+b            19
aa
bb              77

Does the evidence indicate that these two genes are linked?
Explain (what do you expect if they are not linked?).

If so what is the map distance between aand
b? (show your wok)

Are the alleles in the heterozygous parent in coupling or
repulsion?  How can you tell?