Katie set up 15 rows of chairs in the cafeteria for her school's talent competition. in the first 10 rows, she set up 30 chairs on the left side of the middle aisle and x chairs on the right side. in the last 5 rows, she set up 20 chairs on the left side of the middle aisle and y chairs on the right side to make room for the sound crew.

The mean finish time was 185.52 with a standard deviation of 0.327 minute. the winning car driven by chris finished in 185.13. the previous year race had a mean finish time of 110.3 with a standard deviation of 0.106. the winning car that year driven by karen finished in 110.13 minutes. find their respective z-scores. chris - z-score karen “- z-score