Please answer this: Extract the answer to the question from the following context. Question: Why did Bell feel he was vindicated? Context: The question of priority for the variable resistance feature of the telephone was raised by the examiner before he approved Bell's patent application. He told Bell that his claim for the variable resistance feature was also described in Gray's caveat. Bell pointed to a variable resistance device in Bell's previous application in which Bell described a cup of mercury, not water. Bell had filed the mercury application at the patent office a year earlier on February 25, 1875, long before Elisha Gray described the water device. In addition, Gray abandoned his caveat, and because he did not contest Bell's priority, the examiner approved Bell's patent on March 3, 1876. Gray had reinvented the variable resistance telephone, but Bell was the first to write down the idea and the first to test it in a telephone.
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Answer: Bell described a cup of mercury, not water


Please answer this: Extract the answer to the question from the following context. Question: Why was Bell encouraged about the metal detector? Context: Bell is also credited with developing one of the early versions of a metal detector in 1881. The device was quickly put together in an attempt to find the bullet in the body of U.S. President James Garfield. According to some accounts, the metal detector worked flawlessly in tests but did not find the assassin's bullet partly because the metal bed frame on which the President was lying disturbed the instrument, resulting in static. The president's surgeons, who were skeptical of the device, ignored Bell's requests to move the president to a bed not fitted with metal springs. Alternatively, although Bell had detected a slight sound on his first test, the bullet may have been lodged too deeply to be detected by the crude apparatus.
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Answer: worked flawlessly in tests


Please answer this: Extract the answer to the question from the following context. Question: What is the major difference between prokaryote and eukaryote genome? Context: Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.
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Answer:
junk DNA