Plan out functionality and UI (if needed) for US3 feature

[AliceeLe]

Estimated effort: 1-1.5 hours Dependencies: None Acceptance criteria: Brainstorm documentation and rough wireframe for that feature

[AliceeLe]

What we agree is that

• For the backend: Add a new field into the database called answeredByProf. Then, I'll update the APIs to make changes.
• For the frontend: Add a grey box called answered. It'll display a green tick if it is answered by a prof or TA. If not, it'll display a red cross.