Problem: Multiracial American:

For African Americans, the one-drop rule was a significant factor in ethnic solidarity. African Americans generally shared a common cause in society regardless of their multiracial admixture, or social/economic stratification. Additionally, African Americans found it, near, impossible to learn about their Indigenous American heritage as many family elders withheld pertinent genealogical information. Tracing the genealogy of African Americans can be a very difficult process, especially for descendants of Indigenous Americans, because African Americans who were slaves were forbidden to learn to read and write, and a majority of Indigenous Americans neither spoke English, nor read or wrote it.

What was a factor in ethnic solidarity for whites?
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A: unanswerable

Problem: Charleston, South Carolina:

The City of Charleston Police Department, with a total of 452 sworn officers, 137 civilians, and 27 reserve police officers, is South Carolina's largest police department. Their procedures on cracking down on drug use and gang violence in the city are used as models to other cities to do the same.[citation needed] According to the final 2005 FBI Crime Reports, Charleston crime level is worse than the national average in almost every major category. Greg Mullen, the former Deputy Chief of the Virginia Beach, Virginia Police Department, serves as the current Chief of the Charleston Police Department. The former Charleston police chief was Reuben Greenberg, who resigned August 12, 2005. Greenberg was credited with creating a polite police force that kept police brutality well in check, even as it developed a visible presence in community policing and a significant reduction in crime rates.

How many reserve police officers don't the Charleston Police Department have?
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A: unanswerable

Problem: Jehovah%27s Witnesses:

Witnesses believe that a "little flock" go to heaven, but that the hope for life after death for the majority of "other sheep" involves being resurrected by God to a cleansed earth after Armageddon. They interpret Revelation 14:15 to mean that the number of Christians going to heaven is limited to exactly 144,000, who will rule with Jesus as kings and priests over earth. Jehovah's Witnesses teach that only they meet scriptural requirements for surviving Armageddon, but that God is the final judge. During Christ's millennial reign, most people who died prior to Armageddon will be resurrected with the prospect of living forever; they will be taught the proper way to worship God to prepare them for their final test at the end of the millennium.

Jehovah Witnesses interrupted Revelation 14:1-5 to limit heaven goers to exactly what number?
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A: 144,000

Problem: Film speed:

Film speed is used in the exposure equations to find the appropriate exposure parameters. Four variables are available to the photographer to obtain the desired effect: lighting, film speed, f-number (aperture size), and shutter speed (exposure time). The equation may be expressed as ratios, or, by taking the logarithm (base 2) of both sides, by addition, using the APEX system, in which every increment of 1 is a doubling of exposure; this increment is commonly known as a "stop". The effective f-number is proportional to the ratio between the lens focal length and aperture diameter, the diameter itself being proportional to the square root of the aperture area. Thus, a lens set to f/1.4 allows twice as much light to strike the focal plane as a lens set to f/2. Therefore, each f-number factor of the square root of two (approximately 1.4) is also a stop, so lenses are typically marked in that progression: f/1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, etc.

What is the effective f-number proportional to?
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A:
the ratio between the lens focal length and aperture diameter