Please answer this: Extract the answer to the question from the following context. Question: In which edition did Darwin address Mivart's objections? Context: There were serious scientific objections to the process of natural selection as the key mechanism of evolution, including Karl von Nageli's insistence that a trivial characteristic with no adaptive advantage could not be developed by selection. Darwin conceded that these could be linked to adaptive characteristics. His estimate that the age of the Earth allowed gradual evolution was disputed by William Thomson (later awarded the title Lord Kelvin), who calculated that it had cooled in less than 100 million years. Darwin accepted blending inheritance, but Fleeming Jenkin calculated that as it mixed traits, natural selection could not accumulate useful traits. Darwin tried to meet these objections in the 5th edition. Mivart supported directed evolution, and compiled scientific and religious objections to natural selection. In response, Darwin made considerable changes to the sixth edition. The problems of the age of the Earth and heredity were only resolved in the 20th century.
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Answer: sixth edition

Please answer this: Extract the answer to the question from the following context. Question: Why might Bell have wanted to experiment with hearing devices? Context: Bell's father, grandfather, and brother had all been associated with work on elocution and speech, and both his mother and wife were deaf, profoundly influencing Bell's life's work. His research on hearing and speech further led him to experiment with hearing devices which eventually culminated in Bell being awarded the first U.S. patent for the telephone in 1876.[N 4] Bell considered his most famous invention an intrusion on his real work as a scientist and refused to have a telephone in his study.[N 5]
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Answer: both his mother and wife were deaf

Please answer this: Extract the answer to the question from the following context. Question: Who made the less extreme claim, Popper or Bartley? Context: Popper held that rationality is not restricted to the realm of empirical or scientific theories, but that it is merely a special case of the general method of criticism, the method of finding and eliminating contradictions in knowledge without ad-hoc-measures. According to this view, rational discussion about metaphysical ideas, about moral values and even about purposes is possible. Popper's student W.W. Bartley III tried to radicalise this idea and made the controversial claim that not only can criticism go beyond empirical knowledge, but that everything can be rationally criticised.
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Answer:
Popper