Oklahoma
Most Eastern - Alaska Most Western - Alaska Alaska crosses 180˚ longitude, making it a part of the Eastern Hemisphere. This action makes Alaska the most eastern state in the US by a long shot. Alaska is also obviously the most western state.
Alaska, which also has the eastern most point
Alaska
Alaska is the most northern state. Hawaii is the most southern state. Since Alaska's Aleutian Islands lie across the 180th Meridian they lie in both the Eastern and Western Hemispheres. That makes Alaska both the most eastern and most western state also. The International Dateline bends around the Aeulitians, the 180th Meridian does not.
Russia is located in the Eastern and Western himispheres. It is also located in the Nortern hemisphere.
Believe it or not it is Alaska. Alaska is the most northern, most eastern, and most western state. Hawaii is the most southern. Alaska divides the eastern and western hemisphere at the International Dateline or End Meridian (180 degrees longitude), making it qualify for east and west. The Prime meridiam (0 degrees longitude) is located in Greenwich England.
Almost all of the USA is in the western hemisphere, with just a small fraction of the state of Alaska in the eastern one.
Western Hemisphere
Most of it is, but several islands that belong to the USA are in the eastern hemisphere. So technically the USA is located in the western AND in the eastern hemisphere.
western
The majority of the US is located in the western hemisphere. The Prime Meridian, which determines the division between the eastern and western hemispheres, runs through the state of Alaska, meaning that most of the country is to the west of this line.