Don’t worry. You likely wouldn’t remember even if you were taught. 5280 feet/mile is just not worth the brain space. Neither is 8 pints/gallon. I don’t think you would convert between the two often enough to make it useful information to just know.

And I do have to look up those prefixes for the less used ones. It’s exa then peta or peta then exa and what’s bigger than them? What’s smaller than nano? I don’t remember because it rarely comes up. But I’m in tech, so it’s starting to more.