In the middle of the Pacific
china china tokyo
You would be stranded indeed, at sea, about 183 miles north of the Indonesian city of Jayapura on the north coast of the island of New Guinea. And by the way, the "140 degrees east" coordinate is your "longitude".
The prime Meridian is 0 degrees longitude.
The longitude of the State of Missouri is 89 degrees 6'W to 95 degrees 42'W. The Latitude is 36 degrees N to 40 degrees 42'W. The longitude and Latitude of the Missouri River would depend on what location you are researching.
The maximum degree of latitude is 90 degrees north and south, so 180 degrees latitude does not exist. If you meant 180 degrees longitude, then the answer would be that the International Date Line, a major line of longitude, is located there.
Australia
Tallahassee
That would be Greenwich.
20000
Since you did not specify the directions of the latitude and longitude lines, the best assumption would be 15 degrees north latitude and 100 degrees east longitude. However, there is no capital city located there, and none at the other combinations. It is actually Chainat province in Thailand.
The coordinates 15 degrees north latitude and 75 degrees east longitude are located in Asia.