question: measuring the hardness of minerals requires doing what to them?
choices.text: Trigonometry cartilage feedback Cladistics osculum damaging surface treatment
choices.label: A B C D E F G H
fact2: Another type of damage is a scratch.
combinedfact: measuring the hardness of minerals requires damaging them
formatted_question: measuring the hardness of minerals requires doing what to them? (A) Trigonometry (B) cartilage (C) feedback (D) Cladistics (E) osculum (F) damaging (G) surface (H) treatment