Thanks for the question! So I’m assuming you’re asking about the video, which is interesting—I haven’t seen it, but I wouldn’t have analyzed this one by trying to place a PH block, since there isn’t even necessarily a PH block (assuming you’re referring to physics and history). Actually, I just realized you might be referring to the geology physics block, so I’ll assume you’re talking about that.
So why don’t you put GP in the C and D block? Well, say we do. Then the two languages have to be lower than a C grade. But they also have to be consecutive, they can’t be the same grade (rule 2). But if that’s true, that means one is a D, and the other is an E. Uh oh! We were told that we can’t have any failing grades, but putting GP in the CD block forces a failing grade. So that’s why we can’t put them in CD.
Hope this helps! Feel free to ask any other questions that you might have.
