Please help been stuck on this problem for 20 minutes!!

Class -Geometry chapter 10 circles

Book-Geometry a common core curriculum

When a valve is open 281 gallons of water go through it in one hour the number of gallons that would go through in 94 hours is

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?

The result of which expression will best estimate the actual product of (-4/5) x (3/5) x (-6/7) x (5/6) (i need an expression not an answer)