Here is a question about this article: While LEDs have the advantage over fluorescent lamps that they do not contain mercury, they may contain other hazardous metals such as lead and arsenic. Regarding the toxicity of LEDs when treated as waste, a study published in 2011 stated: "According to federal standards, LEDs are not hazardous except for low-intensity red LEDs, which leached Pb [lead] at levels exceeding regulatory limits (186 mg/L; regulatory limit: 5). However, according to California regulations, excessive levels of copper (up to 3892 mg/kg; limit: 2500), lead (up to 8103 mg/kg; limit: 1000), nickel (up to 4797 mg/kg; limit: 2000), or silver (up to 721 mg/kg; limit: 500) render all except low-intensity yellow LEDs hazardous."
What is the answer to this question: What LEDs are considered safer than any other?
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So... low-intensity yellow LEDs

Here is a question about this article: Wang, Strkalj et al. (2003) examined the use of race as a biological concept in research papers published in China's only biological anthropology journal, Acta Anthropologica Sinica. The study showed that the race concept was widely used among Chinese anthropologists. In a 2007 review paper, Strkalj suggested that the stark contrast of the racial approach between the United States and China was due to the fact that race is a factor for social cohesion among the ethnically diverse people of China, whereas "race" is a very sensitive issue in America and the racial approach is considered to undermine social cohesion - with the result that in the socio-political context of US academics scientists are encouraged not to use racial categories, whereas in China they are encouraged to use them.
What is the answer to this question: What is race a factor of for the ethnically diverse people of China?
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So... social cohesion

Here is a question about this article: General gymnastics enables people of all ages and abilities to participate in performance groups of 6 to more than 150 athletes. They perform synchronized, choreographed routines. Troupes may consist of both genders and are not separated into age divisions. The largest general gymnastics exhibition is the quadrennial World Gymnaestrada which was first held in 1939. In 1984 Gymnastics for All was officially recognized first as a Sport Program by the FIG (International Gymnastic Federation), and subsequently by national gymnastic federations worldwide with participants that now number 30 million.
What is the answer to this question: What kind of routines do general gymnastic groups perform?
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So...
synchronized, choreographed routines