So if you cross a heterozygous white and a homozygous black, draw a punnet square. So the box is a 2 by 2 with Ww on the top two and ww on the side to. So in the top left corner, it would be Ww, top right, ww, bottom left, Ww, and bottom right, ww. So the possible phenotypes is half and half Ww and ww. This means that two of the potential phenotypes are Ww and ww, both occurring 50% of the time