 President Biden has a busy day today, and so does former President Donald Trump. They're preparing for their first debate. Unlike past debates, there will be no live audience and mics will be muted while the other candidate speaks. We'll have live special coverage of the CNN presidential debate simulcast starting at 9 p.m. Eastern, 6 p.m. Pacific. You can listen live on your local NPR station at NPR.org or on the NPR app.