It took mary 1.5 hours to bicycle 39km. then she slowed down and took another 3 hours to bicycle 51 km more. find her average speed for the trip.
(total 8 points; 4 points for the answer, 2 points for the units labeled and 2 points for work shown or explanation)

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?