text:  President Biden has landed in Georgia ahead of his presidential debate tonight with former President Trump. The format will be the same, but the rules will be different. CBS's Matt Piper explains. Each candidate's microphone will be muted except when it's his turn to speak. There will also be no studio audience to chime in with hoots, hollers and jeers. There will be two commercials, but they cannot meet with their teams during those breaks.