Based on this information, what is Rollo's phenotype for the whisker type trait?

 - straight whiskers
 - curved whiskers
You need to determine Rollo's phenotype for the whisker type trait. First, consider the alleles in Rollo's genotype for the whisker type gene. Then, decide whether these alleles are dominant or recessive.
The allele for straight whiskers (H) is dominant over the allele for curved whiskers (h). This means H is a dominant allele, and h is a recessive allele.
Rollo's genotype of Hh has one dominant allele and one recessive allele. An organism with at least one dominant allele for a gene will have the dominant allele's version of the trait. So, Rollo's phenotype for the whisker type trait must be straight whiskers.