Answer:
the probability that Mika will have a widow's peak is 100%
Step-by-step explanation:
Assuming that the parents are both heterozygous for the trait (i.e. they each carry one dominant and one recessive allele for the hairline), the Punnett square for their offspring would be:
| W w
--|--------
W | WW Ww
w | Ww ww
Where W represents the dominant allele for a straight hairline and w represents the recessive allele for a widow's peak.
Since both of Mulan's parents have widow's peaks, they must each carry at least one copy of the recessive allele (i.e. they are both Ww).
Therefore, Mulan must have inherited one recessive allele from each of her parents (i.e. she is also Ww).
To calculate the probability that Mika (presumably Mulan's offspring) will have a widow's peak, we would need to know the genotypes of Mika's other parent.
If the other parent is also heterozygous (Ww), the probability that Mika will have a widow's peak is 25% (i.e. there is a 1 in 4 chance that Mika will inherit two copies of the recessive allele).
If the other parent is homozygous for the dominant allele (WW), the probability that Mika will have a widow's peak is 0% (i.e. Mika will inherit one dominant allele from each parent and will have a straight hairline).
If the other parent is homozygous for the recessive allele (ww), the probability that Mika will have a widow's peak is 100% (i.e. Mika will inherit one recessive allele from each parent and will have a widow's peak).