Mendel crossed two plants that were heterozygous for purple flower color. which genotypes could he have used to represent the cross? pp ´ pp pp ´ pp pp ´ pp pp ´ pp

The answer is Pp Pp.

If we imagine that plant has two alleles for the trait and if P represents dominant allele, and p represents recessive allele, then genotypes are:
PP - dominant homozygous, which contains both dominant alleles
pp - recessive homozygous, which contains both recessive alleles
Pp - heterozygous, which contains both dominant and recessive alleles