If it's an answer you can give in 2 seconds or in 5 minutes, just don't answer it. If you are one of the very few who knows the answer then it's valuable and it has a price. Also, just because you think an answer is easy doesn't mean it is for the other person, in that case they have to pay for the knowledge. I get asked by customers at work some very easy basic questions. If they don't know those, then either they're too lazy to find out themselves or they want a quick answer. In either case we charge them. Some answers take me 2 seconds, that costs them $100. (My company charges that rate not me
).