Extract the answer to the question from the following context. Question: What separates an executive agreement from a sole executive agreement? Context: In the United States, the term "treaty" has a different, more restricted legal sense than exists in international law. United States law distinguishes what it calls treaties from executive agreement, congressional-executive agreements, and sole executive agreements. All four classes are equally treaties under international law; they are distinct only from the perspective of internal American law. The distinctions are primarily concerning their method of approval. Whereas treaties require advice and consent by two-thirds of the Senators present, sole executive agreements may be executed by the President acting alone. Some treaties grant the President the authority to fill in the gaps with executive agreements, rather than additional treaties or protocols. And finally, congressional-executive agreements require majority approval by both the House and the Senate, either before or after the treaty is signed by the President.
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Answer: their method of approval

Extract the answer to the question from the following context. Question: Are there more denominations listed or congregations in the National Presbyterian Church? Context: The biggest Presbyterian church is the National Presbyterian Church in Mexico (Iglesia Nacional Presbiteriana de Mexico), which has around 2,500,000 members and associates and 3000 congregations, but there are other small denominations like the Associate Reformed Presbyterian Church in Mexico which was founded in 1875 by the Associate Reformed Church in North America. The Independent Presbyterian Church and the Presbyterian Reformed Church in Mexico, the National Conservative Presbyterian Church in Mexico are existing churches in the Reformed tradition.
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Answer: congregations

Extract the answer to the question from the following context. Question: Did Oklahoma produce less of its electricity from coal or natural gas? Context: Oklahoma is the nation's third-largest producer of natural gas, fifth-largest producer of crude oil, and has the second-greatest number of active drilling rigs, and ranks fifth in crude oil reserves. While the state ranked eighth for installed wind energy capacity in 2011, it is at the bottom of states in usage of renewable energy, with 94 percent of its electricity being generated by non-renewable sources in 2009, including 25 percent from coal and 46 percent from natural gas. Oklahoma has no nuclear power. Ranking 13th for total energy consumption per capita in 2009, Oklahoma's energy costs were 8th lowest in the nation.
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Answer:
coal