Here is a question about this article: Important geological concepts were established as naturalists began studying the rock formations of the Alps in the 18th century. In the mid-19th century the now defunct theory of geosynclines was used to explain the presence of "folded" mountain chains but by the mid-20th century the theory of plate tectonics became widely accepted.
What is the answer to this question: What theory was more widely accepted by the mid-20th century? 
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So... the theory of plate tectonics


Here is a question about this article: Early in 1953, the French asked Eisenhower for help in French Indochina against the Communists, supplied from China, who were fighting the First Indochina War. Eisenhower sent Lt. General John W. "Iron Mike" O'Daniel to Vietnam to study and assess the French forces there. Chief of Staff Matthew Ridgway dissuaded the President from intervening by presenting a comprehensive estimate of the massive military deployment that would be necessary. Eisenhower stated prophetically that "this war would absorb our troops by divisions."
What is the answer to this question: What was John W. O'Daniel's nickname?
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So... Iron Mike


Here is a question about this article: The ReWritable Audio CD is designed to be used in a consumer audio CD recorder, which will not (without modification) accept standard CD-RW discs. These consumer audio CD recorders use the Serial Copy Management System (SCMS), an early form of digital rights management (DRM), to conform to the United States' Audio Home Recording Act (AHRA). The ReWritable Audio CD is typically somewhat more expensive than CD-RW due to (a) lower volume and (b) a 3% AHRA royalty used to compensate the music industry for the making of a copy.
What is the answer to this question: Which is less expensive, the ReWritable Audio CD or a CD-RW?
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So...
CD-RW