a company rented a computer $800 a month. 5 years later the treasurer that if the company had purchased the computer and paid $100 maintenance charge the company would have saved $1000. what was the purchase price for the computer?

Can someone me with my hwplz(only the circled ones)

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?

A3-dimensional figure has a square base and 4 lateral faces that meet at a point. explain the difference between the cross sections when a slice is made perpendicular to the base through the vertex, and when a slice is made perpendicular to the base and not through the vertex