In the offspring obtained from two black mice, there were 75% black and 25% white mice. What are the genotypes of parents?

Aa and Aa
The law of splitting (the second law of Mendel).
Mendel grew plants from the hybrid pea seeds (Aa), which he self-pollinated, and sowed the resulting seeds again. The result was a second generation of hybrids, or F2 hybrids. Among the latter, splitting was found for each pair of alternative characters in a ratio of about 3: 1, i.e. 75% of the plants had dominant characters (purple flowers, yellow seeds, smooth seeds, etc.) and one 25% had recessive (white flowers , green seeds, wrinkled seeds, etc.).

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