Really Fast Delivery Services has the collected the following information about operating expenditures for its delivery truck fleet for the past five years:

Year Miles Operating Costs

2013 55,000 $188,500

2014 70,000 $214,000

2015 50,000 $180,000

2016 65,000 $205,500

2017 85,000 $239,500

Using the high-low method, what is the cost estimate for variable costs for 2018?

a. $1.50

b. $1.70

c. $1.29

d. $2.00