I'm curious. Normally I don't get to ask questions, but I have something, and all the right people in the room. I've been incredibly impressed with what you shared with us today.
We know that CO2 is climbing, and we know that at some point it's toxic to humans. Do we have a sense of where that line is? We know what it would take to kill someone with CO2, but what is happening out there? We have these levels climbing. Do we know when it gets to the point that people are starting to be affected in their functioning and in their health? Do we have a sense of CO2 and its toxicity and where the levels are? Is anybody doing a study on that?