What is the formula that gives the average rate of change of the function z(x) = -6^x +2 + 3 on the interval -1 less than or equal to x less than or equal to 2?

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?

Through non-collinear points there is exactly one plane.

Awasher and a dryer cost $701 combined. the washer costs $51 more than the dryer. what is the cost of the dryer?