Final answer:
The Tablinum in an upper class Roman house was a small room separated from the atrium by a wooden screen or curtain and was used as an office for meeting with clients privately.
Step-by-step explanation:
The Tablinum in an upper class Roman house was a small room separated from the atrium by a wooden screen or curtain. It was typically used as an office for meeting with clients privately. This room contained family records and portraits, and served as a private space for important business meetings.