Burger King is letting you decide how you want its ever-changing “2 for $5” promo. For a limited time, mix and match 2 sandwiches for $5. Choose from the new Extra Long Cheeseburger, Original Chicken, Big Fish and Big King sandwiches. Of course, you must purchase two to get the discount. (If not, you’ll pay full price for just one sandwich. With some of the sandwiches costing around $4 at regular price, why not buy two?) At the discounted price, if you’re really hungry, you just might be able to eat two — just skip the fries and soda. Or, better yet, treat a friend or co-worker. The line-up changes every few months, so check the menu first for the special before ordering.