Question: How to heat a knife to cut thru plastic, rope and other hard materials

  Options: 
 A. Using a soldering iron, remove the tip from the iron and remove the blade from the Exacto knife. Insert the blade holder from the knife into the soldering iron and then put the blade back into the Exacto knife. Heat the knife on a safe, flame resistant surface like a piece of paper.
 B. Using a soldering iron, remove the tip from the iron and remove the blade from the Exacto knife. Insert the blade holder from the knife into the soldering iron and then put the blade back into the Exacto knife. Heat the knife on a safe, flame resistant surface like a ceramic tile.
Answer: B