Speedy Inc is a shipping service and has observed the following delivery costs over the past few months:

Month Mileage in km Delivery costs
1 7250 $ 26,143

2 8160 $ 27,626

3 4250 $21253

4 3260 $19,639

5 7530 $26599

6 2540 $ 18,465

7 12760 $ 35,124

8 15670 $ 39,867

9 38520 $ 77,113

10 98520 $174,913

Leverage Excel to prepare a Scatter graph, in good form, and analyze whether the mileage is a key driver of the costs? What is the suggested Excel cost formula for this cost?