Which expression can be used to convert 80 US dollars (USD) to Australian dollars (AUD)? 1 USD = 1.0343 AUD 1 AUD = 0.9668 USD 80 U S D times StartFraction 0.9668 U S D Over 1 A U D EndFraction 80 U S D times StartFraction 1.0343 U S D Over 1 A U D EndFraction 80 U S D times StartFraction 0.9668 A U D Over 1 U S D EndFraction 80 U S D times StartFraction 1.0343 A U D Over 1 U S D EndFraction Alexis bought x boxes of cereal for $3 each, including tax, and paid with a $20 bill. Which expression represents the total amount of change she should receive? 20 – 3x (3 – 20)x 3x – 20 (20 – 3)x

Abottled water distributor wants to estimate the amount of water contained in 1-gallon bottles purchased from a nationally known water bottling company. the water bottling company’s specifications state that the standard deviation of the amount of water is equal to 0.02 gallon. a random sample of 50 bottles is selected, and the sample mean amount of water per 1-gallon bottle is 0.995 gallon a. construct a 99% confidence interval estimate for the popula-tion mean amount of water included in a 1-gallon bottle. b. on the basis of these results, do you think that the distributor has a right to complain to the water bottling company? why? c. must you assume that the population amount of water per bottle is normally distributed here? explain. d. construct a 95% confidence interval estimate. how does this change your answer to (b)?