Problem: Charleston, South Carolina:

The early settlement was often subject to attack from sea and land, including periodic assaults from Spain and France (both of whom contested England's claims to the region), and pirates. These were combined with raids by Native Americans, who tried to protect themselves from so-called European "settlers," who in turn wanted to expand the settlement. The heart of the city was fortified according to a 1704 plan by Governor Johnson. Except those fronting Cooper River, the walls were largely removed during the 1720s.

The minority of the fort walls were removed in what decade?
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A: unanswerable


Problem: New York City:

New York grew in importance as a trading port while under British rule in the early 1700s. It also became a center of slavery, with 42% of households holding slaves by 1730, more than any other city other than Charleston, South Carolina. Most slaveholders held a few or several domestic slaves, but others hired them out to work at labor. Slavery became integrally tied to New York's economy through the labor of slaves throughout the port, and the banks and shipping tied to the South. Discovery of the African Burying Ground in the 1990s, during construction of a new federal courthouse near Foley Square, revealed that tens of thousands of Africans had been buried in the area in the colonial years.

In 1730, what percentage of New York households were slave-holding?
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A: 42%


Problem: Mammal:

In 1997, the mammals were comprehensively revised by Malcolm C. McKenna and Susan K. Bell, which has resulted in the McKenna/Bell classification. Their 1997 book, Classification of Mammals above the Species Level, is the most comprehensive work to date on the systematics, relationships, and occurrences of all mammal taxa, living and extinct, down through the rank of genus, though recent molecular genetic data challenge several of the higher level groupings. The authors worked together as paleontologists at the American Museum of Natural History, New York. McKenna inherited the project from Simpson and, with Bell, constructed a completely updated hierarchical system, covering living and extinct taxa that reflects the historical genealogy of Mammalia.

What was the book written by Simpson?
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A: unanswerable


Problem: Renewable energy commercialization:

Tax shifting has been widely discussed and endorsed by economists. It involves lowering income taxes while raising levies on environmentally destructive activities, in order to create a more responsive market. For example, a tax on coal that included the increased health care costs associated with breathing polluted air, the costs of acid rain damage, and the costs of climate disruption would encourage investment in renewable technologies. Several Western European countries are already shifting taxes in a process known there as environmental tax reform.

What involves lowering income taxes while raising levies?
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A:
Tax shifting