3 Minutes
 Pete and BJ have cultured the bacteria in a petri dish. They isolate a bacterial colony that started from a single bacterium that came into contact with the petri dish from the air. The colony had been growing for forty-eight hours when they disbursed the entire colony in 100 mililiters of sterile water. They took 0.1 mililiters of that and disbursed it in 99.9 mililiters of sterile water. They put one drop of that under a four square centimeter cover slip and look at it under a microscope. The volume of a drop is 0.1 mililiter. The area of the field of vision with the oil immersion lens they are using is 0.04 square centimeters. They count an average of 50 bacteria in the field of vision. How many bacteria are in the colony?
HINT: Figure out what fraction of the original colony they had under the field of vision, then multiply their count by the reciprocal. Refer to the table. The population doubles every hour.
A) 5 million
B) 50 million
C) 500 million
D) 5 billion
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