Al Spray recently opened Al's Bar in the University District. Because of licensing restrictions, the only liquor he can sell is beer. The average price of beer at Al's Bar is $3.00 per glass, and each glass costs Al an average of $ 2.00. Al has hired a bartender and waiter at $ 4 comma 500 and $ 500 per month, respectively. His rent, utilities, and other fixed operating costs are $ 2 comma 000 per month.If Al sells only beer, how many glasses of beer does he have to sell each month to make a monthly profit of 10% of sales? (