Final answer:
The project manager should store the new request in the requirements documentation as it is the appropriate place for detailing specific project needs and conditions that must be met.
Step-by-step explanation:
The best place for the project manager to store a new request depends on the nature of the request. If the request is for a change that affects the project's deliverables or the product characteristics, it should be documented in the requirements documentation. This is because requirements documentation captures the specific needs or conditions that must be met for the project to be successful. On the other hand, if the request is related to how the team will maintain or assess the quality of the deliverables, then it would be more appropriate to document in the quality documentation. The scope statement includes a detailed description of the project's deliverables, boundaries, and acceptance criteria, making it less suitable for storing new requests which may or may not affect the overall project scope. Lastly, the requirements management plan describes how requirements will be analyzed, documented, and managed throughout the project and is not the place to store individual requests.