The table below shows how a boutique brewery's total cost of producing craft beer kegs changes as its monthly output increases.
| Output (kegs per month) | Total cost per month (£) |
|---|---|
| 0 | 80,000 |
| 1,000 | 220,000 |
| 2,000 | 320,000 |
| 3,000 | 400,000 |
What is the average fixed cost of producing 2,000 kegs of craft beer per month?
£80
£40
£120
£160
