Answer:
Bright white fur 3/4
Black fur 3/16
brown fur 1/16
Explanation:
From the Punnet's square analysis (see the attached image);
A_B_ and A_bb will always give offsprings with bright white fur since allele A always mask the effect of B.
aaB_ will always give offsprings with black fur since allele a does not produce any protein.
aabb will give offsprings with brown fur since b codes for brown fur colour.
Hence, the phenotypic ratio of the offspring will be;
Bright white fur 3/4
Black fur 3/16
brown fur 1/16