The life span of a certain bacteria is 22 hours, with a standard deviation of 1.5 hours. In a random sampling of 5,000 bacteria, how many would you expect survive between 19 and 22 hours A) 3400
B) 1700
C) 4750
D) 2375

The weekly amount spent by a company for travel has an approximately normal distribution with mean = $550 and standard deviation = $40. a) what is the probability that the actual weekly expense will exceed $570 for more than 20 weeks during the next year? (note: one year = 52 weeks) b) what is the probability that actual weekly expenses exceed $580 for 10 or more, but 16 or fewer weeks during the next year?