In this task, you're given passages that contain mentions of the quantity of a particular object and are supposed to find out the answer for a given question. Craft one correct answer to the question given in input. Make sure your correct answer is consistent with the context, and properly gives the exact number relating to the query.
 In your answer, use as few words as possible from the given context. To be less repetitive, please vary your language for each question.

Q: Sentence: The Convention came into force as international law on 12 January 1951 after the minimum 20 countries became parties. At that time however, only two of the five permanent members of the UN Security Council were parties to the treaty: France and the Republic of China. The Soviet Union ratified in 1954, the United Kingdom in 1970, the People's Republic of China in 1983 (having replaced the Taiwan-based Republic of China on the UNSC in 1971), and the United States in 1988. This long delay in support for the Convention by the world's most powerful nations caused the Convention to languish for over four decades. Only in the 1990s did the international law on the crime of genocide begin to be enforced. 
Question: The delay in support by certain powerful members meant the Convention was largely powerless for over how many decades?

A: four
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Q: Sentence: Simultaneously with these conflicts, bison, a keystone species and the primary protein source that Native people had survived on for centuries were being destroyed. Some estimates say there were over 13 million bison in Montana in 1870. In 1875, General Philip Sheridan pleaded to a joint session of Congress to authorize the slaughtering of herds in order to deprive the Indians of their source of food. By 1884, commercial hunting had brought bison to the verge of extinction; only about 325 bison remained in the entire United States. 
Question: About how many bison were in Montana in 1870?

A: over 13 million
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Q: Sentence: In April 2013, the Infectious Disease Society of America (IDSA) reported that the weak antibiotic pipeline does not match bacteria's increasing ability to develop resistance. Since 2009, only 2 new antibiotics were approved in the United States. The number of new antibiotics approved for marketing per year declines continuously. The report identified seven antibiotics against the Gram-negative bacilli (GNB) currently in phase 2 or phase 3 clinical trials. However, these drugs do not address the entire spectrum of resistance of GNB. Some of these antibiotics are combination of existent treatments: 
Question: How many antibiotics have been created in the last 7 years?

A:
2
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