"Two. All my favorite sports involve water - salt or frozen. Skiing, surfing, swimming, and scuba diving."

"Hmm, I'm a good swimmer and I know how to snorkel, but I've never tried scuba diving."

"If you're interested, I know a bloke that runs certification classes."

"I'm interested, but free time might be a problem."

Mark considered, then smiled.

"Let's check with Napoleon. There's a decent chance they might consider it a useful skill for you to learn. If not, we'll eventually figure something out."

"Sounds worth a shot. Certainly couldn't hurt to ask."