Problem: Geography of the United States:

The Great Plains come to an abrupt end at the Rocky Mountains. The Rocky Mountains form a large portion of the Western U.S., entering from Canada and stretching nearly to Mexico. The Rocky Mountain region is the highest region of the United States by average elevation. The Rocky Mountains generally contain fairly mild slopes and wider peaks compared to some of the other great mountain ranges, with a few exceptions (such as the Teton Mountains in Wyoming and the Sawatch Range in Colorado). The highest peaks of the Rockies are found in Colorado, the tallest peak being Mount Elbert at 14,440 ft (4,400 m). The Rocky Mountains contain some of the most spectacular, and well known scenery in the world. In addition, instead of being one generally continuous and solid mountain range, it is broken up into a number of smaller, intermittent mountain ranges, forming a large series of basins and valleys.

What mountains generally contain steep slopes and narrow peaks?
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A: unanswerable


Problem: Flowering plant:

The evolution of seed plants and later angiosperms appears to be the result of two distinct rounds of whole genome duplication events. These occurred at 319 million years ago and 192 million years ago. Another possible whole genome duplication event at 160 million years ago perhaps created the ancestral line that led to all modern flowering plants. That event was studied by sequencing the genome of an ancient flowering plant, Amborella trichopoda, and directly addresses Darwin's "abominable mystery."

Who coined the term "abominable mystery"?
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A: Darwin


Problem: Germans:

The Napoleonic Wars were the cause of the final dissolution of the Holy Roman Empire, and ultimately the cause for the quest for a German nation state in 19th-century German nationalism. After the Congress of Vienna, Austria and Prussia emerged as two competitors. Austria, trying to remain the dominant power in Central Europe, led the way in the terms of the Congress of Vienna. The Congress of Vienna was essentially conservative, assuring that little would change in Europe and preventing Germany from uniting. These terms came to a sudden halt following the Revolutions of 1848 and the Crimean War in 1856, paving the way for German unification in the 1860s. By the 1820s, large numbers of Jewish German women had intermarried with Christian German men and had converted to Christianity. Jewish German Eduard Lasker was a prominent German nationalist figure who promoted the unification of Germany in the mid-19th century.

What declined after the fall of the Holy Roman Empire?
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A: unanswerable


Problem: Dissolution of the Soviet Union:

In the first session of the new Congress of People's Deputies, from May 25 to June 9, hardliners retained control but reformers used the legislature as a platform for debate and criticism – which was broadcast live and uncensored. This transfixed the population; nothing like this freewheeling debate had ever been witnessed in the U.S.S.R. On May 29, Yeltsin managed to secure a seat on the Supreme Soviet, and in the summer he formed the first opposition, the Inter-Regional Deputies Group, composed of Russian nationalists and liberals. Composing the final legislative group in the Soviet Union, those elected in 1989 played a vital part in reforms and the eventual breakup of the Soviet Union during the next two years.

Who used the legislative session to debate and criticize?
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A:
reformers