Final answer:
The completion time for the MacArthur lock is not specified in the provided information.
Step-by-step explanation:
The completion time for the MacArthur lock is not specified in the provided information. However, it is important to note that General MacArthur was involved in various military operations during his career, such as the retaking of the Philippines and the Inchon invasion during the Korean War. These operations required different timeframes and strategies, and the completion time for the lock itself is not mentioned.