NEW YORK (AP) — Amazon is aiming to kill the supermarket checkout line. The online retailing giant is opening its first cashier-less grocery store, the latest sign that Amazon is serious about shaking up the $800 billion grocery industry. At the new store, opening Tuesday in Seattle, shoppers can grab milk or eggs and walk out without checking out or opening their wallets. Shoppers scan a smartphone app to enter the store. Cameras and sensors track what's taken off shelves. Items are charged to an Amazon account after leaving.