Lavania is studying the growth of a population of fruit flies in her laboratory. After 6 days she had nine more than five times as many fruit flies as when she began the study. If she observes 20 fruit flies on the first day of the study, write and evaluate an expression to find the population of fruit flies Lavania observed after 6 days
a. write an expression for the population of fruit flies Lavania observed after 6 days
b. find the population of fruit flies Lavania observed after 6 days