Oh, I know this one! It's from "Illusions of Grandeur".

Nick: "I'm faster than a speeding bullet!"

Chris: "No way."

Nick: "Okay, but I'm faster than you. And stronger, too."

Chris: "No way.[...] What is it?"

Nick: "How should I know."

***

Here's the next one:

"-'- --- ---- - --- ----- ----- --- ----."

"-- ---- -- ---- -- ---?"

"-- ---- -- --."

"--- ----- --- -- ---?"

"-- ----- - --- -- ---. --- --- ----."


The only known quantity that moves faster than
light is the office grapevine. (from Nan's fabulous Home series)