Your question is Oracle Concepts and Tuning Deep Dive. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Describe the node eviction and what causes it, explain what OCLUMON is, and walk me through how you would tune a query and back up a NOARCHIVELOG database without shutting it down.