OAK BROOK, Ill. - McDonald's is trying to modernize its image by rolling out delivery and promising fresh beef in Quarter Pounders. But for **w, $1 sodas are helping get people in the door. The company said Tuesday that discounted drinks and a new line of pricier burgers helped boost sales in its flagship U.S. market by 3.9 per cent at existing locations during the second quarter. CEO Steve Easterbrook has been working on transforming the chain's ...