Problem: There were serious scientific objections to the process of natural selection as the key mechanism of evolution, including Karl von Nägeli'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.
What was Darwin's concession to Karl von Nägel's objections?
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Answer: Darwin conceded that these could be linked to adaptive characteristics


Problem: The Washington National Records Center (WNRC), located in Suitland, Maryland is a large warehouse type facility which stores federal records which are still under the control of the creating agency. Federal government agencies pay a yearly fee for storage at the facility. In accordance with federal records schedules, documents at WNRC are transferred to the legal custody of the National Archives after a certain point (this usually involves a relocation of the records to College Park). Temporary records at WNRC are either retained for a fee or destroyed after retention times has elapsed. WNRC also offers research services and maintains a small research room.
When do researchers transfer documents to the WNRC?
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Answer: unanswerable


Problem: An alloy is a mixture of either pure or fairly pure chemical elements, which forms an impure substance (admixture) that retains the characteristics of a metal. An alloy is distinct from an impure metal, such as wrought iron, in that, with an alloy, the added impurities are usually desirable and will typically have some useful benefit. Alloys are made by mixing two or more elements; at least one of which being a metal. This is usually called the primary metal or the base metal, and the name of this metal may also be the name of the alloy. The other constituents may or may not be metals but, when mixed with the molten base, they will be soluble, dissolving into the mixture.
What is an alloy composed of?
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Answer:
two or more elements