In the course of the month, a company suffered a burglary and a quantity of inventory was stolen. The table gives the company’s figures for the month: opening inventory, at cost $30000$; purchases $210000$; revenue $330000$; closing inventory, at cost $4000$. A gross profit of $30\%$ on all sales had been made. What was the cost of the inventory lost in the burglary?
- A$4000$
- B$5000$
- C$9000$
- D$13000$