What are the gametes in males?

Cattle with brown fur and cattle with white fur will produce a reddish roan calf . when examined closely, the calf show about an even number of brown hairs and white hairs that give a reddish appearance when viewed from far away. the fact that both the brown fur allele and the white fur allele are expressed equally in the offspring is an example of

Why has two different alleles for the same trait?

Which of these reproductive method is the only on available to mosses and fernsspores