In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.
Q: Sentence1: Pat sat down to his desk at work to type an email. Sentence2: When he got to writing his name, he realized the letter P was missing. Sentence3: He asked his co-workers if they knew anything about it. Sentence4: They all laughed and said that it must be a prank. Sentence5: Pat grabbed another keyboard from storage to use for the day.
A:
Pat, Co-workers