1. A batch reactor with nutrient-rich medium is used to culture two different mammalian cell species. Both species are at the same concentration when batch growth begins. They are at their maximum growth rate, which is assumed to be exponential. (15 pts) Td of species 1=3 hours and Td of species 2=5 hours a. After 12 hours of incubation/growth, what is the ratio of X1/X2 ? b. How long should the mixed culture undergo batch growth in order to obtain X1/X2 =15? c. Assuming that each species uses equal mass of the same substrate for their growth over a 10 hour period, what would be the ratio of growth yields after 10 hours