Problem: Please answer a question about the following article about Compact disc:
The Compact Disc is an evolution of LaserDisc technology, where a focused laser beam is used that enables the high information density required for high-quality digital audio signals. Prototypes were developed by Philips and Sony independently in the late 1970s. In 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. After a year of experimentation and discussion, the Red Book CD-DA standard was published in 1980. After their commercial release in 1982, compact discs and their players were extremely popular. Despite costing up to $1,000, over 400,000 CD players were sold in the United States between 1983 and 1984. The success of the compact disc has been credited to the cooperation between Philips and Sony, who came together to agree upon and develop compatible hardware. The unified design of the compact disc allowed consumers to purchase any disc or player from any company, and allowed the CD to dominate the at-home music market unchallenged.
To what does the compact disc owe its prosperity?
A: cooperation between Philips and Sony
Problem: Please answer a question about the following article about Railway electrification system:
3 kV DC is used in Belgium, Italy, Spain, Poland, the northern Czech Republic, Slovakia, Slovenia, South Africa, Chile, and former Soviet Union countries (also using 25 kV 50 Hz AC). It was formerly used by the Milwaukee Road from Harlowton, Montana to Seattle-Tacoma, across the Continental Divide and including extensive branch and loop lines in Montana, and by the Delaware, Lackawanna & Western Railroad (now New Jersey Transit, converted to 25 kV AC) in the United States, and the Kolkata suburban railway (Bardhaman Main Line) in India, before it was converted to 25 kV 50 Hz AC.
What does the railway system of US use DC or AC?
A: AC
Problem: Please answer a question about the following article about Anthropology:
Along with dividing up their project by theoretical emphasis, anthropologists typically divide the world up into relevant time periods and geographic regions. Human time on Earth is divided up into relevant cultural traditions based on material, such as the Paleolithic and the Neolithic, of particular use in archaeology.[citation needed] Further cultural subdivisions according to tool types, such as Olduwan or Mousterian or Levalloisian help archaeologists and other anthropologists in understanding major trends in the human past.[citation needed] Anthropologists and geographers share approaches to Culture regions as well, since mapping cultures is central to both sciences. By making comparisons across cultural traditions (time-based) and cultural regions (space-based), anthropologists have developed various kinds of comparative method, a central part of their science.
Olduwan, Mousterian, and Levalloisian are all types of what?
A: tool
Problem: Please answer a question about the following article about Kathmandu:
The base of the stupa has 108 small depictions of the Dhyani Buddha Amitabha. It is surrounded with a brick wall with 147 niches, each with four or five prayer wheels engraved with the mantra, om mani padme hum. At the northern entrance where visitors must pass is a shrine dedicated to Ajima, the goddess of smallpox. Every year the stupa attracts many Tibetan Buddhist pilgrims who perform full body prostrations in the inner lower enclosure, walk around the stupa with prayer wheels, chant, and pray. Thousands of prayer flags are hoisted up from the top of the stupa downwards and dot the perimeter of the complex. The influx of many Tibetan refugees from China has seen the construction of over 50 Tibetan gompas (monasteries) around Boudhanath.
What are gompas?
A:
monasteries