If B and b are the two alleles , B + b = 1 and B ^2 +2 Bb + b ^2 = 1.
If 16% of mice are homozygous black , B ^ 2 =0 .16, meaning B = 0 .4 and b = 1 - 0. 4 = 0 .6 . Answer = Notice how you don't even need to know that 24% of the mice are heterozygous .
These are macrophytes that grow entire in the freshwater and become fossilized by the calcification oozes, going back to the Paleozoic era about 250 million years ago.
And they are unicellular to multi-cellular organisms also found in moist terrestrial habitats.