Please help me just using gars- growth and development, adaptation, reproduction and structure

Abnormal softening of a gland is known as

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?

About __ of the mass of the cell is water