Q: In this task, you're given the title of a story consisting of five sentences, numbered 1 through 5. Your job is to determine which two sentences need to be swapped sentences in order to make a story that makes complete sense and is befittingly titled. Indicate your answer using the numbers of the two sentences in order, such as '34' or '25'. The first digit refers to the sentence which should come first in the story.
Title: The Dentist. Sentence 1: As she was biting into a piece of popcorn, she heard a crack. Sentence 2: She got an extra large bucket to share with her friends. Sentence 3: Susan was eating popcorn at the movie theater. Sentence 4: She had chipped her tooth on a hard kernel. Sentence 5: Karen went to the dentist the next day to have her tooth repaired.
A:
13