Answer:
B. 36,450
Explanation:
To determine the number of bacteria after 4.5 hours, we need to calculate the number of 45-minute intervals in 4.5 hours and then multiply the initial population by the growth factor.
4.5 hours is equivalent to 4.5 * 60 = 270 minutes.
Since the bacteria triple in population every 45 minutes, we can divide the total time (270 minutes) by the interval time (45 minutes) to get the number of intervals: 270 / 45 = 6 intervals.
The growth factor is 3, as the bacteria triple in population.
To find the final population, we can use the formula:
Final Population = Initial Population * (Growth Factor)^(Number of Intervals)
Final Population = 50 * (3)^6
Final Population = 50 * 729
Final Population = 36,450
Therefore, the correct answer is B. 36,450 bacteria.