Here is a question about this article: In China, urbanization increased as the population grew and as the division of labor grew more complex. Large urban centers, such as Nanjing and Beijing, also contributed to the growth of private industry. In particular, small-scale industries grew up, often specializing in paper, silk, cotton, and porcelain goods. For the most part, however, relatively small urban centers with markets proliferated around the country. Town markets mainly traded food, with some necessary manufactures such as pins or oil. Despite the xenophobia and intellectual introspection characteristic of the increasingly popular new school of neo-Confucianism, China under the early Ming dynasty was not isolated. Foreign trade and other contacts with the outside world, particularly Japan, increased considerably. Chinese merchants explored all of the Indian Ocean, reaching East Africa with the treasure voyages of Zheng He.
What is the answer to this question: Name one of the reasons urbanization grew in China.
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So... population grew


Here is a question about this article: Clodius formed armed gangs that terrorised the city and eventually began to attack Pompey's followers, who in response funded counter-gangs formed by Titus Annius Milo. The political alliance of the triumvirate was crumbling. Domitius Ahenobarbus ran for the consulship in 55 BC promising to take Caesar's command from him. Eventually, the triumvirate was renewed at Lucca. Pompey and Crassus were promised the consulship in 55 BC, and Caesar's term as governor was extended for five years. Crassus led an ill-fated expedition with legions led by his son, Caesar's lieutenant, against the Kingdom of Parthia. This resulted in his defeat and death at the Battle of Carrhae. Finally, Pompey's wife, Julia, who was Caesar's daughter, died in childbirth. This event severed the last remaining bond between Pompey and Caesar.
What is the answer to this question: Who was responsible for an expedition against the Parthian Kingdom?
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So... Crassus


Here is a question about this article: 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 is the answer to this question: What device uses infrared LEDs to measure oxygen saturation?
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So...
Pulse oximeters