Thank you, Chair.
And thanks to the witnesses for being here today.
It's been mentioned here previously, Mr. Crump, and you mentioned black carbon, which, as I understand, is the incomplete combustion of fossil fuels, biofuels, and biomass. With that in mind, do you have any thoughts on how to reduce black carbon, complete the combustion process, considering this planet seems to be so reliant on some of the fossil fuels, such as metallurgical coal?