Problem: A sociological comparative study by the Pew Research Center found that Jehovah's Witnesses in the United States ranked highest in statistics for getting no further than high school graduation, belief in God, importance of religion in one's life, frequency of religious attendance, frequency of prayers, frequency of Bible reading outside of religious services, belief their prayers are answered, belief that their religion can only be interpreted one way, belief that theirs is the only one true faith leading to eternal life, opposition to abortion, and opposition to homosexuality. In the study, Jehovah's Witnesses ranked lowest in statistics for having earned a graduate degree and interest in politics.
What do few Jehovah's Witnesses earn?
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Answer: a graduate degree


Problem: The second major event of the early reign of Abd al-Malik was the construction of the Dome of the Rock in Jerusalem. Although the chronology remains somewhat uncertain, the building seems to have been completed in 692, which means that it was under construction during the conflict with Ibn al-Zubayr. This had led some historians, both medieval and modern, to suggest that the Dome of the Rock was built as a destination for pilgrimage to rival the Kaaba, which was under the control of Ibn al-Zubayr.
When was the Kaaba under construction?
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Answer: unanswerable


Problem: Many sensor systems rely on light as the signal source. LEDs are often ideal as a light source due to the requirements of the sensors. LEDs are used as motion sensors, for example in optical computer mice. The Nintendo Wii's sensor bar uses infrared LEDs. Pulse oximeters use them for measuring oxygen saturation. Some flatbed scanners use arrays of RGB LEDs rather than the typical cold-cathode fluorescent lamp as the light source. Having independent control of three illuminated colors allows the scanner to calibrate itself for more accurate color balance, and there is no need for warm-up. Further, its sensors only need be monochromatic, since at any one time the page being scanned is only lit by one color of light. Since LEDs can also be used as photodiodes, they can be used for both photo emission and detection. This could be used, for example, in a touchscreen that registers reflected light from a finger or stylus. Many materials and biological systems are sensitive to, or dependent on, light. Grow lights use LEDs to increase photosynthesis in plants, and bacteria and viruses can be removed from water and other substances using UV LEDs for sterilization.
What video game console doesn't use infrared LEDs?
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Answer:
unanswerable