By Alex Lang New York (Knewz) — The average price of gas could be north of $4.50 by the end of the week, an industry expert warned. On May 16, the average price in the U.S. for a gallon of gas sat at $4.46, according to GasBuddy. An app that tracks fuel supplies and gas prices. That figure is up slightly more than 15 cents from a week ago. The national average is up nearly 40 percent from a month ago, GasBuddy noted. “Those filling their tanks last week saw another jolt at the pump, as both gasoline and diesel prices continued their multi-week rally,” said Patrick De Haan, head of petroleum an…