Answer:
There are two phenotype: black and white.
As we can observe that in heterozygous condition (Ww) the phenotype is white. Hence, white is a dominant character whereas black is a recessive character which will be expressed only under homozygous recessive condition i.e. (ww).
Now, Ww will form two types of gametes W and w whereas ww will form only one type of gamete i.e. w.
Cross (mentioned in the attached file)
There are two white and two black offspring. Hence, the phenotypic ration (white:black) would be 2:2 which comes out to be 1:1.
Similarly, there are two Ww and two ww. Hence, genotypic ratio (Ww:ww) would be 2:2 which comes out to be 1:1.