Problem: Separation of powers under the United States Constitution:

The first six presidents of the United States did not make extensive use of the veto power: George Washington only vetoed two bills, James Monroe one, and John Adams, Thomas Jefferson and John Quincy Adams none. James Madison, a firm believer in a strong executive, vetoed seven bills. None of the first six Presidents, however, used the veto to direct national policy. It was Andrew Jackson, the seventh President, who was the first to use the veto as a political weapon. During his two terms in office, he vetoed twelve bills—more than all of his predecessors combined. Furthermore, he defied the Supreme Court in enforcing the policy of ethnically cleansing Native American tribes ("Indian Removal"); he stated (perhaps apocryphally), "John Marshall has made his decision. Now let him enforce it!"

How many bills did Andrew Jackson veto to make him the least likely president to veto a bill?
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A: unanswerable


Problem: Friedrich Hayek:

Hayek had a long-standing and close friendship with philosopher of science Karl Popper, also from Vienna. In a letter to Hayek in 1944, Popper stated, "I think I have learnt more from you than from any other living thinker, except perhaps Alfred Tarski." (See Hacohen, 2000). Popper dedicated his Conjectures and Refutations to Hayek. For his part, Hayek dedicated a collection of papers, Studies in Philosophy, Politics, and Economics, to Popper and, in 1982, said that "ever since his Logik der Forschung first came out in 1934, I have been a complete adherent to his general theory of methodology". Popper also participated in the inaugural meeting of the Mont Pelerin Society. Their friendship and mutual admiration, however, do not change the fact that there are important differences between their ideas.

Which of Popper's works was the first to grasp Hayek's attention?
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A: Logik der Forschung


Problem: Classical music:

Electric instruments such as the electric guitar, the electric bass and the ondes Martenot appear occasionally in the classical music of the 20th and 21st centuries. Both classical and popular musicians have experimented in recent decades with electronic instruments such as the synthesizer, electric and digital techniques such as the use of sampled or computer-generated sounds, and instruments from other cultures such as the gamelan.

What type of musicians besides classical have experimented with electronic instruments?
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A: popular


Problem: Mammal:

Therapsids descended from pelycosaurs in the Middle Permian, about 265 million years ago, and became the dominant land vertebrates. They differ from basal eupelycosaurs in several features of the skull and jaws, including: larger temporal fenestrae and incisors which are equal in size. The therapsid lineage leading to mammals went through a series of stages, beginning with animals that were very like their pelycosaur ancestors and ending with probainognathian cynodonts, some of which could easily be mistaken for mammals. Those stages were characterized by:

When did basal eupelycosaurs descend from pelycosaurs?
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A:
unanswerable