In April and May, a business recorded the following figures. Units made and sold: April $1000$, May $1200$. Total revenue: April $\$50\,000$, May unknown. Total contribution: April $\$22\,000$, May unknown. Total profit: April $\$8000$, May $\$10\,500$. The selling price per unit and total fixed costs stayed unchanged. What was the change in the variable cost per unit?
- Adecrease $\$0.75$
- Bdecrease $\$1.58$
- Cincrease $\$0.75$
- Dincrease $\$1.58$