PLEASE HELP Which system of equations represents the following situation? Mrs. Stephens bought 3 containers of yogurt and 5 oranges for $2.79. The next week she bought 4 containers of yogurt and 7 oranges for $3.81, at the same prices.

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.