A minor league baseball team wants to sell ad space on their outfield wall to local businesses. The team originally thinks about charging $250 per ad. However, the local businesses know that the more ads there are, the less focus each individual ad will get, so they’re not willing to pay as much per ad if they know there will be more of them. The team does market research and finds that they can get $250 for one ad, $245 per ad for two ads, $240 per ad for three ads, and so on. The total revenue from all the outfield banners is calculated using the expression a(250-5(a-1)). Interpret what the expression 250-5(a-1) represents, and explain your reasoning.