CASLAN are you good at math 56+6789-4X10076=?

What are the soultion(s) to the quadratic equation 40- x^2=0

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?

Solve this problem! extra ! 3025/5.5 = a/90.75