In dogs, black fur (B) is dominant over yellow fur (b). A heterozygous black dog is matted with a yellow dog. Do a Punnett square to show the cross and predict the offspring.

Since one of the dogs is a heterozygous dog, it means that the dog isn’t completely have black fur. Yes, the dog has the gene, but he also has the recessive gene of yellow fur. Making his yellow fur gene be recessive and get covered by the black fur dominant gene. (Bb). With the other parent has pure yellow fur recessive gene (bb). The punnet square below explains more clearly what I mean.

This means that there is a 50/50 chance of getting some puppies with full yellow fur but there is another 50/50 chance of then having the dominant gene of black fur but still having the yellow fur gene hidden.