Extract the answer to the question from the following context. Question: What was made with the National Security Act of 1947? Context: The United States Air Force (USAF) is the aerial warfare service branch of the United States Armed Forces and one of the seven American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on 18 September 1947 under the National Security Act of 1947. It is the most recent branch of the U.S. military to be formed, and is the largest and one of the world's most technologically advanced air forces. The USAF articulates its core functions as Nuclear Deterrence Operations, Special Operations, Air Superiority, Global Integrated ISR, Space Superiority, Command and Control, Cyberspace Superiority, Personnel Recovery, Global Precision Attack, Building Partnerships, Rapid Global Mobility and Agile Combat Support.
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Answer: USAF


Extract the answer to the question from the following context. Question: Where is Washington university located? Context: In 1867, the university opened the first private nonsectarian law school west of the Mississippi River. By 1882, Washington University had expanded to numerous departments, which were housed in various buildings across St. Louis. Medical classes were first held at Washington University in 1891 after the St. Louis Medical College decided to affiliate with the University, establishing the School of Medicine. During the 1890s, Robert Sommers Brookings, the president of the Board of Trustees, undertook the tasks of reorganizing the university's finances, putting them onto a sound foundation, and buying land for a new campus.
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Answer: west of the Mississippi River


Extract the answer to the question from the following context. Question: How does DNA become constricted from RNA? Context: Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.
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Answer:
silencers