Definition: Given the Question and Answer pair, detect whether the answer is acceptable or not. Denote acceptable answer as "yes", otherwise denote as "no". An acceptable answer is consistent with the context in question, detailed, long, and uses general knowledge of English. Answers that are not definite and suggest a variety of options are not acceptable answers.
Input: Question: The context: Customer pays for some service 100$. If he chooses an option X, we charge him 20$ more, so 120$ in total. As a programmer I want my variables to have meaningful names. How would you call this 20$ in this context? I consider two words: markup (but it is more related to the business than customer IMHO) and surcharge. 
Answer: I would think that what ever is driving the cost/price of the "Extra" should be kept as its own identity. If we choose an extra option on the back of a product, like cable mentioned above, we know what we are asking for and therefore we are not being charged anything additional. The cable company would report separately on these two items, as they should. So, that said, where will you report this income? As a product sale, a service offered, or are you simply wanting to charge one person more than another for the same product/service?.

no