In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: Besides sheriffs and posses, who helped keep the peace?, Context: In the American Old West, policing was often of very poor quality.[citation needed] The Army often provided some policing alongside poorly resourced sheriffs and temporarily organized posses.[citation needed] Public organizations were supplemented by private contractors, notably the Pinkerton National Detective Agency, which was hired by individuals, businessmen, local governments and the federal government. At its height, the Pinkerton Agency's numbers exceeded those of the United States Army.[citation needed]

Answer: Army

Question: How did CBS Records form a relationship with Tree International Publishing?, Context: In 1989, CBS Records re-entered the music publishing business by acquiring Nashville music publisher Tree International Publishing for more than $30 million.

Answer: acquiring

Question: What keeps people from getting sick?, Context: In more recent applications, hydrogen is used pure or mixed with nitrogen (sometimes called forming gas) as a tracer gas for minute leak detection. Applications can be found in the automotive, chemical, power generation, aerospace, and telecommunications industries. Hydrogen is an authorized food additive (E 949) that allows food package leak testing among other anti-oxidizing properties.

Answer:
E 949