 Complete the following phrase:  Resuming her operations in Vietnamese waters on 22 March, William H. Standley began a difficult and demanding line period. Tensions in Korea had erupted, causing the U.S. naval forces in the Far East to go on alert. North Korean and U.S. forces had exchanged fire briefly near the demilitarized zone between the two Koreas on 11 March, and, on 15 April, 