This question invites you to suggest a solution or system that addresses the travel requirements of Facebook employees. This could include arrangements for accommodations, transportation logistics, reimbursement processes, and ensuring adherence to company policies and safety protocols. In tackling this task, take into account all facets of employee travel—before the trip (such as planning and booking), during the trip (including access to company resources and safety), and after the trip (like reimbursements). Additionally, consider the various user roles, including Employee, HR, Manager, and Finance teams; each will engage with the solution, but they have distinct needs and permissions. A comprehensive response would identify these primary users, outline their needs, and suggest how the system could fulfill those requirements. It's also important to address practical limitations, such as budget, time, and complexity, and possibly propose trade-offs.