Please HELP ITS A GRADE AND TIMED I WILL MARK BRAINLIEST

Me find the measure to side c and the process to solve the problem you appreciate it : )

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $32.09. find the probability that a randomly selected bill will have an amount greater than $155, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

Interpret the following expression (5y^2-7)^3/(2y)^2