Dear AT&T

dear at&t: thank you for the internet service. I think you should know, though, that your bills don't make any sense. I passed both algebra and calculus (not to mention 5th grade) with flying colors, so I promise you I can both add and subtract. However, I cannot make heads or tails of your calculations, even with the help of a calculator and my roommate, who is a chemistry major. Please explain yourself.
sincerely,
E.O.