For August, the figures for selling 6\,000 units were given below, per unit: selling price $40$, variable costs $22$, fixed costs $12$, profit $6$. In September, the selling price was cut by $10\%$. Which sales level was required in September to earn the same total profit as in August?
- A$5\,143$ units
- B$6\,600$ units
- C$7\,715$ units
- D$9\,000$ units