On Sunday night, I purchased a bullfrog from a corner coffeeshop for Monday’s lesson on Osmosis, diffusion and Surface area to volume ratio. The uncle at the counter was confused as to why I wanted just two legs from my anuran meal. He curtly said $6. Sensing his displeasure as he mumbled that they usually sold them in pairs, I explained I was using it to teach a class. That changed everything and he even gave me a $2 discount. He made it known to the cook and busy waitress of the very useful frog.