What is the value of this expression 1/3-5

Is the following relation a function? x y 1 4 −1 −2 3 10 5 16 yes no

Which equation requires the division property of equality to be solved?

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?