i) I think four gametes are possible in either a male or a female. That is; GY, gY, Gy, and gy.This is because both traits are heterozygous which means for a certain gene there are two different alleles. While in the case of homozygous there would only be one type of gametes since for a given gene there are two similar alleles. ii) I think crossing over or recombination could cause the alleles that are linked with the wing color and the eye color genes to be exchanged between the two chromosomes in a pair, thus, resulting to new combinations of alleles. The final result would then be an increase in possible genetic variation.