1.who was the commander of the u.s. navy in the pacific?

2.where did the japanese strike after pearl harbor?

http://en.wikipedia.org/wiki/Chester_W._Nimitz

http://en.wikipedia.org/wiki/Pacific_War#Japanese_offensives.2C_1941.E2.80.9342

i need concrete answer please

If you read the first couple of paragraphs of each of those web sites, you'll find your concrete answers. The first one is especially obvious.

To find the answer to question 1, you can utilize search engines or trusted online sources. The commander of the U.S. Navy in the Pacific during World War II was Admiral Chester W. Nimitz.

To find the answer to question 2, you can follow a similar process. The Japanese struck multiple targets after the attack on Pearl Harbor. Some notable locations include the Philippines, Guam, Wake Island, and the British colonies of Hong Kong, Malaya, and Singapore.