Why are invasive species dangerous to the environment?

Ialready know the answers to these questions and they are on the attachment. but i just need to know why that answer is the correct one. plz asap! this is for a report that i need to email by 10!

Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. an incomplete dominance cross is performed between a bird that is homozygous for red feathers and a bird that is homozygous for blue feathers. purple offspring result. then, two of the purple offspring are crossed. according to the punnett square for this cross, how many of the offspring from the second cross will have a feather color that results from incomplete dominance? 1 in 4 2 in 4 3 in 4 4 in 4

1. in a certain species of plant, the color purple (p) is dominant to the color white (p). according the punnett square, what is the probability of and offspring being white? 50%25%0%100% 2. in a certain species of plant, the color purple (p) is dominant to the color white (p). according the punnett square, what is the probability of and offspring being white? 0%100%50%25%(picture 1 is for question 1, and picture 2 is for question 2)