Problem: Hunter-gatherer:

Starting at the transition between the Middle to Upper Paleolithic period, some 80,000 to 70,000 years ago, some hunter-gatherers bands began to specialize, concentrating on hunting a smaller selection of (often larger) game and gathering a smaller selection of food. This specialization of work also involved creating specialized tools, like fishing nets and hooks and bone harpoons. The transition into the subsequent Neolithic period is chiefly defined by the unprecedented development of nascent agricultural practices. Agriculture originated and spread in several different areas including the Middle East, Asia, Mesoamerica, and the Andes beginning as early as 12,000 years ago.

What was the change in gathering?
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A: a smaller selection

Problem: Transistor:

Discrete transistors are individually packaged transistors. Transistors come in many different semiconductor packages (see image). The two main categories are through-hole (or leaded), and surface-mount, also known as surface-mount device (SMD). The ball grid array (BGA) is the latest surface-mount package (currently only for large integrated circuits). It has solder "balls" on the underside in place of leads. Because they are smaller and have shorter interconnections, SMDs have better high-frequency characteristics but lower power rating.

What is the oldest type of semiconductor package?
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A: unanswerable

Problem: Portugal:

The country bounced between socialism and adherence to the neoliberal model. Land reform and nationalizations were enforced; the Portuguese Constitution (approved in 1976) was rewritten in order to accommodate socialist and communist principles. Until the constitutional revisions of 1982 and 1989, the constitution was a highly charged ideological document with numerous references to socialism, the rights of workers, and the desirability of a socialist economy. Portugal's economic situation after its transition to democracy, obliged the government to pursue International Monetary Fund (IMF)-monitored stabilization programs in 197778 and 198385.

In what year was the Portuguese Constitution approved?
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A: 1976

Problem: Karl Popper:

Popper coined the term "critical rationalism" to describe his philosophy. Concerning the method of science, the term indicates his rejection of classical empiricism, and the classical observationalist-inductivist account of science that had grown out of it. Popper argued strongly against the latter, holding that scientific theories are abstract in nature, and can be tested only indirectly, by reference to their implications. He also held that scientific theory, and human knowledge generally, is irreducibly conjectural or hypothetical, and is generated by the creative imagination to solve problems that have arisen in specific historico-cultural settings.

Who argued in favor of the classical observationalist-inductivist account of science?
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A:
unanswerable