The correct answers are:
1. Gulf of Mexico.
2. Maine.
The state of Oklahoma lies in the central part of the United States, in the Great Plains region. It is not a state that comes out on a sea/ocean, thus its landlocked. The closest sea waters are on the south, just after Texas, where the Gulf of Mexico is located.
The state of Maine, on the other hand, is a very small state, and it is located in the northeastern part of the country, and since the state of Oklahoma is located in the southern part of the Great Plains, and in the central part of the country, the state of Maine comes to be located in an northeast direction from it.