A number minus 6 is less than or equal to 21

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?

Which inequality has a dashed boundary line when graphed ?

The ph level of a blueberry is 3.1 what is the hydrogen-ion concentration [h+] for the blueberry