The red-green color blindness is a recessive X-linked trait. The females are not affected unless both the X chromosomes have the affected allele. Mostly, the females are the carriers, and the males are affected as they have only one X chromosome. In the given pedigree, the father of Irene have the normal allele, while her mother is a carrier. However, Irene is neither a carrier nor affected. This means that she carries normal alleles on both X chromosomes. Hence, her allele combination is
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5 is C -- mutation.
I can't read all of 6-- sorry!
7. Succession, 6. Extinction, 5. Niche, 3. Ecosystem, 2. Population, 1. Habitat, 4. Environment, 8. Community