CNBC.com’s MacKenzie Sigalos has the day’s top business news headlines. Pfizer submitted its Covid-19 vaccine to the FDA for emergency authorization today, kicking off the first step of the approval and deployment process. But CNBC’s Bertha Coombs explains how, at the same time, the combination of rising infection and Thanksgiving travel prep is putting a strain on some clinics that offer tests for the virus. Plus, the "After Hours" team dives into the rave reviews for Apple’s new M1 chips….