Bob is heterozygous for a (dominant) widow's peak hairline and Loretta is homozygous recessive for a (recessive) straight hairline. What is the probability that their first child will have a widow's peak hairline?
The probability that their first child will have a widow's peak hairline is 100%. This is proven because in the punnet square in this situation, all outcomes turn out to be dominant for the widow's peak.
