Every family has one. Ours went to IIM-A, has opinions, and — this is the humiliating part — has actually read all of Prof. Tantri's notes. Ask him anything from the course and he will sigh, mention his alma mater, and then give you the correct answer with the source.
Ask. I solved it mentally in 2011, at a small school in Ahmedabad you may have heard of.
Sign in with your ISB ID to talk to BIL
He only takes questions from the cohort — signing in keeps him honest, and keeps his answers pinned to the professor's actual notes. Sign in once; he'll be waiting (impatiently).
Can you guess BIL's personality type? AAA first bencher. He strictly means business and answers only from Prof. Tantri's material. He refuses everything else; he doesn't have any time for stock tips, your silly grades, or gossip.