Answer:
Could you please help me arrange the books?
Step-by-step explanation:
The original sentence in in the imperative mood. This mood is used to give commands, orders, suggestions, or to make requests. Another example of a sentence in the imperative mood is: Don't open the door.
According to the instructions, we must change the sentence into the interrogative mood. This is the mood used to ask questions. To do that without changing the general meaning of the sentence, we can simply add "could you" at the beginning. It makes the sentence interrogative but maintains the request:
Could you please help me arrange the books?