Opportunity cost is essential what the forgone cost of doing something it; it's the alternative choice of what you could have used your time for. To incorporate it into your "Business letter," justifying why you deserve the 2% say that writing this letter I have missed the opportunity to do xxx, thus proving this class and my grade is one of my highest priorities, which is why I deserve the 2%. Something a long those lines, I honestly would of just said something how I came to class everyday, participated to the best of my ability in class, and did my best to the learn the course material, which is why I deserve 2%.