ya this one is super unambiguously PEMDAS
Spoiler alert: they all are
the one that has more of an argument is the one with the division of whether a/b(c) is a / (b * c) or (a / b) * c
No it doesn't, The Distributive Law, a(b+c)=(ab+ac), thus a/b(c)=a/(bxc).
The issue in the U.S. isn't Maths textbooks (same rules as everywhere else), it's poor teaching. U.S. Maths teachers aren't required to have any Maths qualifications, and they've been sliding in world rankings for more than a decade now.