Final answer:
Admiral Chester Nimitz was the Commander of the US Pacific fleet during WW2, and he made a significant contribution by leading the Central Pacific Campaign.
Step-by-step explanation:
Admiral Chester Nimitz was the Commander of the US Pacific fleet during World War II.
He was promoted to Fleet Admiral and became the highest-ranking officer in the navy.
Nimitz made a significant contribution by leading the Central Pacific Campaign, which involved a series of offensives to directly move toward Japan and draw the Imperial Japanese navy into decisive fleet engagements.
This strategy was instrumental in turning the tide of the war in the Pacific.