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: Dunking. Sentence 1: He went for a lay up and jumped high enough to dunk. Sentence 2: Drew went to play basketball with his friends. Sentence 3: Drew was shocked because he had never dunked before. Sentence 4: Drew smiled triumphantly, but everyone else started to laugh. Sentence 5: They had lowered the rim by a foot prior to playing.
A:
21