A entrepreneur purchases a workshop costing $200\,000 in order to produce plastic boxes. During the first year of trading, he pays $70\,000 for materials, hires ten production workers who are paid according to the quantity made (piece rate) at an overall cost of $80\,000, and acquires two delivery vehicles costing $10\,000 each. What is the total amount of his variable costs?
- A$100\,000$
- B$150\,000$
- C$220\,000$
- D$370\,000$