After taking a dose of medication the amount of medicine remaining in a person’s bloodstream in milligrams after x hours can be modeled by the function f(x) = 55( 0.92)^x. find the interpret the given function values and determine an appropriate domain for the function someone please help please

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