 Virginia's governor addressed the Republican National Convention last night, and he made some big promises, not just for America, but for the Commonwealth itself. It is both the heat and the humidity as the wrath of summer continues in the DMV. We're under an excessive heat warning and a heat advisory, depending on where you are today. And some lifestyle changes could help prevent cancer. We dig deeper with CBS News Chief Medical Correspondent Dr. John LaPook at 9.15. 9 o'clock.