Interesting. You're positive the NA isn't actually necessary? I'm curious about these examples. I didn't look closely at it, but PT 71.S1.Q11 seems to be about pollution. Is that the right reference? PT means PrepTest, right?
Under the Resources pull down menu select Logic Game Explanations. Scroll down and you will see the respective PrepTest Icon and to the right of each icon click on the appropriate game you want to review.
https://7sage.com/logic-game-explanations/