Below is a set of at least two related math/science "words" with their letters combined and arranged in alphabetical order. When you successfully unscramble the letters into the component words, there will be can additional word that should be in the set. That additional word is your answer for the set.

Question

e.g. EEEFHNOORRTU unscrambles to ONE, THREE, and FOUR, with TWO being the logical related word that would be your answer.

Set: AAACCDDEEGHINNNORRSSTTTU