Hello!
Answer:
Dominant alleles are represented with an uppercase letter.
Recessive alleles are represented with a lowercase letter.
Explanation: Take for example, “AA”. Both “A’s” in this allele pair are uppercase, so they are dominant alleles. As another example, let’s say an allele pair was “bb”. Since both of the “b’s” are lowercase, they each would be a recessive allele.
I hope this helps you!