FL made me think of Future Law, so that sounded kinda Spacemaster, right?
Then I saw that Advanced Math says to check "3.48 Scientific Skills, FL pg 11"...even more suspicious.
Turns out, I have an old scan of the rules in Spacemaster first edition, where 3.48 is Scientific Skills and 3.5 is Secondary skills.
Since other skills in RMCII point to secondary skills in Character Law, I'd guess the content will be the same, only that they forgot to change that reference in those skills.
I read both and it makes more sense to consider RMCI section 4.3 for all of them, it's just an explanation of that is a secondary skill.