Answer:
1: To make the reader think that Rikki is dead
2: To show how he got to the family (how the family picked him up and took him home)
3: To show how Rikki's life changed and started new
Explanation:
I had a whole unit over this story and it could be any of those answers. So if you want one specific answer all of those should be correct and you can choose the answer you think fits best.
