Qiang drives 15 miles at an average speed of 30 miles per hour. How many additional miles will he have to drive at 55 miles per hour to average 50 miles per hour for the entire trip?<spanclass=′latex−bold′>(A)</span>45<spanclass=′latex−bold′>(B)</span>62<spanclass=′latex−bold′>(C)</span>90<spanclass=′latex−bold′>(D)</span>110<spanclass=′latex−bold′>(E)</span>135