1)Sarah Ouellette has leased a new automobile under a special lease plan. If she drives the car 1,000 miles or less during a one-month period, the lease payment is $250.If the mileage ranges between 1,001 and 1,500 miles, the lease payment becomes $300. If the mileage ranges between 1,501 and 2,000 miles, the lease payment rises to $350

Required:

a)What type of cost is the lease?

b)If sarah only drives the car between 1,200 and 1,400miles per month, then what type of cost does the lease effectively become?