Which absolute magnitude rating would be the dullest? btw it says middle school but this is high school level a-6b. 0c. +2d. -1

Guinea pig coat color is determined by a single gene. the allele for black coat color is dominant to brown. in a cross between twoblack-haired guinea pigs, 20 offspring are born. if both parents were heterozygous, probability would predict that approximately howmany of the 20 offspring would have brown hair?