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: Max had a dead tree in his yard. Sentence2: He decided he needed to cut the tree down. Sentence3: He asked to borrow a chainsaw from a friend. Sentence4: After surveying the area, he toppled the tree into his yard. Sentence5: By cutting the tree in pieces, he had fireplace wood for the winter.
A:
Max, A friend