Problem: Federalism:

The structures of most federal governments incorporate mechanisms to protect the rights of component states. One method, known as 'intrastate federalism', is to directly represent the governments of component states in federal political institutions. Where a federation has a bicameral legislature the upper house is often used to represent the component states while the lower house represents the people of the nation as a whole. A federal upper house may be based on a special scheme of apportionment, as is the case in the senates of the United States and Australia, where each state is represented by an equal number of senators irrespective of the size of its population.

What does the structures of the federal government incorporate?
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A: mechanisms to protect the rights of component states

Problem: Separation of powers under the United States Constitution:

One may claim that the judiciary has historically been the weakest of the three branches. In fact, its power to exercise judicial reviewits sole meaningful check on the other two branchesis not explicitly granted by the U.S Constitution. The U.S. Supreme Court exercised its power to strike down congressional acts as unconstitutional only twice prior to the Civil War: in Marbury v. Madison (1803) and Dred Scott v. Sandford (1857). The Supreme Court has since then made more extensive use of judicial review.

Before the Civil War, the Marbury had exercised its power to strike down what type of acts only twice?
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A: unanswerable

Problem: Nanjing:

A number of sculptural ensembles of that era, erected at the tombs of royals and other dignitaries, have survived (in various degrees of preservation) in Nanjing's northeastern and eastern suburbs, primarily in Qixia and Jiangning District. Possibly the best preserved of them is the ensemble of the Tomb of Xiao Xiu (475518), a brother of Emperor Wu of Liang. The period of division ended when the Sui Dynasty reunified China and almost destroyed the entire city, turning it into a small town.

Who was Xiao Xiu?
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A: a brother of Emperor Wu of Liang

Problem: Animal:

The Ecdysozoa are protostomes, named after the common trait of growth by moulting or ecdysis. The largest animal phylum belongs here, the Arthropoda, including insects, spiders, crabs, and their kin. All these organisms have a body divided into repeating segments, typically with paired appendages. Two smaller phyla, the Onychophora and Tardigrada, are close relatives of the arthropods and share these traits. The ecdysozoans also include the Nematoda or roundworms, perhaps the second largest animal phylum. Roundworms are typically microscopic, and occur in nearly every environment where there is water. A number are important parasites. Smaller phyla related to them are the Nematomorpha or horsehair worms, and the Kinorhyncha, Priapulida, and Loricifera. These groups have a reduced coelom, called a pseudocoelom.

Organisms in the Arthropoda group have bodies that are divided into what?
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A:
repeating segments