The number of yeast cells in a laboratory culture increases rapidly initially but levels off eventually. The population is modeled by the function а n = f(t) = 1 + be-0.90 where t is measured in hours. At time t = 0 the population is 30 cells and is increasing at a rate of 24 cells/hour. Find the values of a and b. a = b = According to this model, what happens to the yeast population in the long run? O The yeast population will shrink to 0 cells. The yeast population will stabilize at 270 cells. The yeast population will stabilize at 135 cells. The yeast population will stabilize at 8 cells. O The yeast population will grow without bound.