In a group of Syrian hamsters, some individuals have straight whiskers and others have curved whiskers. In this group, the gene for the whisker type trait has two alleles. The allele for straight whiskers (H) is dominant over the allele for curved whiskers (h). This Punnett square shows a cross between two Syrian hamsters. What is the probability that a Syrian hamster produced by this cross will be heterozygous for the whisker type gene?