Two utility companies sell electricity in units of kilowatt-hours. The cost of electricity for company P is shown in the table. The cost of electricity for company M can be found by using the equation shown, where y represents the total cost in dollars for x kilowatt-hours of electricity.

Use the information provided to find the unit rate, in dollars per kilowatt-hour, for each company. Show your work or explain your answers.

Find the total cost, in dollars, of buying 2,375 kilowatt-hours of electricity from the least expensive company.