Are these the right answers?...

it takes hundreds of years to become stable.

if you have another question lmk.

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.

this is a good question! i'll do some research and come back when i have the answer!

this is true, assuming that the allele is completely recessive and incomplete dominance is not a factor.