What is the difference, in cells per liter, between the lab result and 10 billion? 0.2 cells per liter
1.2 cells per liter
2 x 10^9 cells per liter
2 x 10^10 cells per liter

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?