I suppose it's a zygote. In haplontic life cycle haploid gametes fuse together creating the zygote (diploid) that promptly divides meiotically creating 4 haplontic cells serving as spores.
Answer: 100%
Explanation:
if the mutation presents autosomal dominant inheritance, each affected individual will show 100% alteration in the protein, thus , being dominant, it is considered that the disease pattern will predominate even if it has genes that do not express it since these will be recessive and canceled by the dominant ones.