Sailor Mouth / Artist Unknown - S2-E15
Trivia: In Sailor Mouth, Squidward's line, "Don't you mean there are only seven?" is a reference to George Carlin's "Seven Words You Can't Say On TV".
Mermaid Man and Barnacle Boy III / Squirrel Jokes - S2-E4
Trivia: Patrick says "I'm thinking in a number between 1 and 100, what is it?". Man-ray says "62". However, in Spanish, he says "72".
The Bully / Just One Bite - S2-E17
Trivia: In "Just One Bite", there was a deleted scene where Squidward enters the Krusty Krab at night. Squidward opens the door, and a bucket of gasoline falls and spills all over the ground. A robotic arm drops a lit match to light the gasoline.
Answer: I believe this is the Season 6 episode "Spongicus".