Someone please help me

Answer this question! 30 points and brainliest! only if you know the answer.

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?

Use composition to determine if (x) or h(x) is the inverse of f(x) for the limited domain x2-1.