Crazy Things Non-Coin Collectors Say

I remember 10th grade chemistry, we did a lab that involved testing how some type of acid reacted with a pre-1982 penny versus a post-1982 penny, the point that the acid would react differently with the different metals.

On the lab report it had a spot to write the years and the city the penny was minted of the two pennies tested, with a note that P = Philidelphia, D = Denver, and no mint mark = Washington, D.C.

We got a bonus point if we pointed out any errors on his handouts, so I told him that no mint mark = P and that pennies don't have P mint marks. He insisted I was wrong, so I had to drop it, and being the nerd I was mad I never got my bonus point! (on the lab I refused to write Washington, D.C. and put no mint mark = Philidelphia, forgot if he wrote anything)

Also mad that on that same handout he had " its' " which I told him was not supposed to have an apostrophe, which he also didn't believe me (It's possessive!). (As you can tell I didn't like this teacher lol).