Problem: Black people:

After the First World War, however, it became apparent that the number of mixed-race people was growing at a faster rate than the white population, and by 1930 fear of the "half-caste menace" undermining the White Australia ideal from within was being taken as a serious concern. Dr. Cecil Cook, the Northern Territory Protector of Natives, noted that:

What did people fear in 1930?
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A: "half-caste menace"


Problem: Great Plains:

The North American Environmental Atlas, produced by the Commission for Environmental Cooperation, a NAFTA agency composed of the geographical agencies of the Mexican, American, and Canadian governments uses the "Great Plains" as an ecoregion synonymous with predominant prairies and grasslands rather than as physiographic region defined by topography. The Great Plains ecoregion includes five sub-regions: Temperate Prairies, West-Central Semi-Arid Prairies, South-Central Semi-Arid Prairies, Texas Louisiana Coastal Plains, and Tamaulipus-Texas Semi-Arid Plain, which overlap or expand upon other Great Plains designations.

What states are in the West-Central Semi-Arid Praries?
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A: unanswerable


Problem: Crucifixion of Jesus:

In Mark 15:25 crucifixion takes place at the third hour (9 a.m.) and Jesus' death at the ninth hour (3 p.m.). However, in John 19:14 Jesus is still before Pilate at the sixth hour. Scholars have presented a number of arguments to deal with the issue, some suggesting a reconciliation, e.g., based on the use of Roman timekeeping in John but not in Mark, yet others have rejected the arguments. Several notable scholars have argued that the modern precision of marking the time of day should not be read back into the gospel accounts, written at a time when no standardization of timepieces, or exact recording of hours and minutes was available, and time was often approximated to the closest three-hour period.

During what time period was Pilate avaliable to be seen?
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A: unanswerable


Problem: Incandescent light bulb:

The spectrum emitted by a blackbody radiator at temperatures of incandescent bulbs does not match the sensitivity characteristics of the human eye; the light emitted does not appear white, and most is not in the range of wavelengths at which the eye is most sensitive. Tungsten filaments radiate mostly infrared radiation at temperatures where they remain solid – below 3,695 K (3,422 °C; 6,191 °F). Donald L. Klipstein explains it this way: "An ideal thermal radiator produces visible light most efficiently at temperatures around 6,300 °C (6,600 K; 11,400 °F). Even at this high temperature, a lot of the radiation is either infrared or ultraviolet, and the theoretical luminous efficacy (LER) is 95 lumens per watt." No known material can be used as a filament at this ideal temperature, which is hotter than the sun's surface. An upper limit for incandescent lamp luminous efficacy (LER) is around 52 lumens per watt, the theoretical value emitted by tungsten at its melting point.

What appears white to the human eye when it is emitted?
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A:
unanswerable