Find length of minor arc in a circle include correct unit

Find an equation of the line perpendicular to the graph.

Use set builder notation to represent the following set: { -3, -2, -1, 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?