8. A Bird in the Hand. Harold talking to the quarterback of The Stallions.
9. Columbo Goes to College. Coop talking with one of his frat bros after a tennis game.
10. The Conspirators. Joe Devlin asking Columbo after Columbo "skins" him at a game of darts.
Here's a picture of the Olympics Poster in Question #6
1. Troubled Waters - Deck Quoits - Columbo to Hayden Danzinger (partially correct)
2. A Matter of Honor - Bullfighting - Señor Montoya speaking to Hector Rangel (CORRECT)
3. Last Salute to the Commodore - Sailing - Swanny speaking to Columbo (partially correct)
4. Any Old Port in a Storm - Diving - Joan Stacey (Ric Carsini's fiancee) to Columbo (CORRECT)
5. Ransom for a Dead Man - Flying - Leslie speaking to Columbo (CORRECT)
6. Try and Catch Me - Olympics Poster (Edmund had all sorts of sports stuff in his apartment) - Abigail Mitchell visiting with Columbo
7. How to Dial A Murder - Pool - Columbo to Dr. Mason (incorrect)
8. A Bird in the Hand - Football - Harold McCain to the QB of the "Stallions" - who were actually wearing Edmonton Eskimos uniforms
9. Columbo Goes to College - Tennis - Coop talking to his frat buddies (CORRECT)
10. The Conspirators - Darts - Joe Devlin to Columbo in the pub after being skinned. (CORRECT)
Congratulations! Well done.