The problem: Answer a question about this article:
The most common symptom of LED (and diode laser) failure is the gradual lowering of light output and loss of efficiency. Sudden failures, although rare, can also occur. Early red LEDs were notable for their short service life. With the development of high-power LEDs the devices are subjected to higher junction temperatures and higher current densities than traditional devices. This causes stress on the material and may cause early light-output degradation. To quantitatively classify useful lifetime in a standardized manner it has been suggested to use L70 or L50, which are the runtimes (typically given in thousands of hours) at which a given LED reaches 70% and 50% of initial light output, respectively.
What could cause early light-output degradation in LEDs?
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The answer: higher junction temperatures

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Beyonce's second solo album B'Day was released on September 5, 2006, in the US, to coincide with her twenty-fifth birthday. It sold 541,000 copies in its first week and debuted atop the Billboard 200, becoming Beyonce's second consecutive number-one album in the United States. The album's lead single "Deja Vu", featuring Jay Z, reached the top five on the Billboard Hot 100 chart. The second international single "Irreplaceable" was a commercial success worldwide, reaching number one in Australia, Hungary, Ireland, New Zealand and the United States. B'Day also produced three other singles; "Ring the Alarm", "Get Me Bodied", and "Green Light" (released in the United Kingdom only).
How many copies did B'Day sell during the first week of its release?
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The answer: 541,000

The problem: Answer a question about this article:
Tandem repeats are usually caused by slippage during replication, unequal crossing-over and gene conversion, satellite DNA and microsatellites are forms of tandem repeats in the genome. Although tandem repeats count for a significant proportion in genome, the largest proportion in mammalian is the other type, interspersed repeats.
What are two examples of tandem repeats in DNA?
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The answer: satellite DNA and microsatellites

The problem: Answer a question about this article:
The American bison is a large bovid which inhabited much of western North America prior to the 1800s, living on the prairies in large herds. However, the vast herds of bison attracted market hunters, who killed dozens of bison for their hides only, leaving the rest to rot. Thousands of these hunters quickly eliminated the bison herds, bringing the population from several million in the early 1800s to a few hundred by the 1880s. Conservation efforts have allowed the population to increase, but the bison remains near-threatened.
What did market hunters leave the parts of the bison they didn't need to do?
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The answer:
rot