Problem: The first commercial LEDs were commonly used as replacements for incandescent and neon indicator lamps, and in seven-segment displays, first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as TVs, radios, telephones, calculators, as well as watches (see list of signal uses). Until 1968, visible and infrared LEDs were extremely costly, in the order of US$200 per unit, and so had little practical use. The Monsanto Company was the first organization to mass-produce visible LEDs, using gallium arsenide phosphide (GaAsP) in 1968 to produce red LEDs suitable for indicators. Hewlett Packard (HP) introduced LEDs in 1968, initially using GaAsP supplied by Monsanto. These red LEDs were bright enough only for use as indicators, as the light output was not enough to illuminate an area. Readouts in calculators were so small that plastic lenses were built over each digit to make them legible. Later, other colors became widely available and appeared in appliances and equipment. In the 1970s commercially successful LED devices at less than five cents each were produced by Fairchild Optoelectronics. These devices employed compound semiconductor chips fabricated with the planar process invented by Dr. Jean Hoerni at Fairchild Semiconductor. The combination of planar processing for chip fabrication and innovative packaging methods enabled the team at Fairchild led by optoelectronics pioneer Thomas Brandt to achieve the needed cost reductions. These methods continue to be used by LED producers.
How much did the early LEDs cost?
The answer is the following: US$200 per unit

Problem: One rescue team reported only 2,300 survivors from the town of Yingxiu in Wenchuan County, out of a total population of about 9,000. 3,000 to 5,000 people were killed in Beichuan County, Sichuan alone; in the same location, 10,000 people were injured and 80% of the buildings were destroyed. The old county seat of Beichuan was abandoned and preserved as part of the Beichuan Earthquake Museum. Eight schools were toppled in Dujiangyan. A 56-year-old was killed in Dujiangyan during a rescue attempt on the Lingyanshan Ropeway, where due to the earthquake 11 tourists from Taiwan had been trapped inside cable cars since May 13. A 4-year-old boy named Zhu Shaowei (traditional Chinese: 朱紹維; simplified Chinese: 朱绍维; pinyin: Zhū Shàowéi) was also killed in Mianzhu City when a house collapsed on him and another was reported missing.
How many residents were killed in Beichuan County?
The answer is the following: 3,000 to 5,000

Problem: As of 2000[update], children and teenagers (0–19 years old) make up 15.1% of the population, while adults (20–64 years old) make up 65% and seniors (over 64 years old) make up 19.9%.
What percent of the population are over 64 years old?
The answer is the following: 19.9%

Problem: Another unofficial but much more well-known mascot is Ronnie "Woo Woo" Wickers who is a longtime fan and local celebrity in the Chicago area. He is known to Wrigley Field visitors for his idiosyncratic cheers at baseball games, generally punctuated with an exclamatory "Woo!" (e.g., "Cubs, woo! Cubs, woo! Big-Z, woo! Zambrano, woo! Cubs, woo!") Longtime Cubs announcer Harry Caray dubbed Wickers "Leather Lungs" for his ability to shout for hours at a time. He is not employed by the team, although the club has on two separate occasions allowed him into the broadcast booth and allow him some degree of freedom once he purchases or is given a ticket by fans to get into the games. He is largely allowed to roam the park and interact with fans by Wrigley Field security.
What did Harry Caray dub Wickers?
The answer is the following:
"Leather Lungs