And so this female individual must be lowercase B lowercase B, and this male must be lowercase B lowercase B. Now what about these two individuals? Well, they can either be uppercase B uppercase B, or they can be uppercase B lowercase B. So we have two different possibilities and we can test both of these possibilities to see if they actually work. Let's begin by assuming that this individual has this genotype and this individual also has that genotype. So in this particular case we can carry out our punish square.