An amusement park is charging $27 for adult tickets (a) and $24 for children’s tickets (c). Last Friday The Amusement park sold 272 tickets and collected 7137 which of the following systems of equations is a correct representation of this data?

Monitors manufactured by tsi electronics have life spans that have a normal distribution with a standard deviation of 1800 hours and a mean life span of 20,000 hours. if a monitor is selected at random, find the probability that the life span of the monitor will be more than 17,659 hours. round your answer to four decimal places.