In watermelons, bitter fruit (b) is dominant over sweet fruit (b), and yellow spots (s) are dominant over no spots (s). the genes for these two characteristics assort independently. a homozygous plant that has bitter fruit and yellow spots is crossed with a homozygous plant that has sweet fruit and no spots. if an f1 plant is backcrossed with the bitter, yellow-spotted parent, what phenotypes and proportions are expected in the offspring?