Please thoroughly explain.

You have a business selling and delivering pizzas to businesses for lunch. You pay $4,000 per month in rent, 320 for utilities, and $2,000 a month for salaries. You also have delivery cars that cost $1,000 per month. Your variable costs are $8 per pizza for ingredients and $4 per pizza for delivery costs You sell the pizzas for $20 each. Round up if necessary ? What is the number of pizzas you need to sell to break even for the month