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Problem 1: (10 points) When an antibiotic is introduced into a culture of 50,000 bacteria, the number of bacteria decreases exponentially. After 9 hours, there are only 20,000 bacteria. a) Write an exponential equation to express the decay function y in terms of time t in hours. Round decay constant to two dacimal places. Box your final equation. b) In how many hours will half the number of bacteria remain? If necessary, round answer to two decimal places. Include units in your