Answer:
B) On the same place on the same chromosome.
Explanation:
Both alleles are located on the same chromosome and present at the same place because genes come in pair. Each pair of gene is located at a specific place on a chromosome. If the two alleles present at a specific location are similar to each other, it is called homo-zygous while on the other hand, if both alleles are different from one another, they are considered as hetero-zygous.
20 percent.
Since one strand is 20, the opposite that would connect with it (Thymine) would have the same amount so the total would be 100.
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