A certain population of bacteria doubles every 60 minutes. Beginning with 50 bacteria in the culture, the population can be represented by the function A=50(2)^t, where A is the number of bacteria after t number of hours. Which of these is the appropriate domain for the function A in terms of given context? a. all integers greater than or equal to 50
b. all integers greater than or equal to 0
c. all real numbers greater than 50
d. all real numbers greater than or equal to 0