You are given a sentence and a question. You're expected to write the correct answer based on the sentence.

Sentence: A tree trunk is thicker then a tree leaf. Question: Which part of the tree is the stronger one?
trunk

Sentence: Ben wants to put up a poster in the school hall and he wants it to be resistant to tearing. Question: What should he make the poster on?
cardboard

Sentence: Kory set up two slides in his backyard. One slide is metal and doesn't create much friction, while the other slide is wood and creates more friction. Question: If Kory slides down both slides, which one will he go quicker on?

metal slide