I consider myself to be comfortable using metric units. I know the standard prefixes and how to convert between units. Having said that, I did not get a perfect score on this quiz the first time I took it. You know how you can talk yourself out of the right answer? Yeah... I did that. Let's see if you will too. You might want to review the metric prefixes or you can just be bold and take the quiz. If you score perfectly, no gloating is allowed.