romikgosai/squad_modified huggingface dataset:
Much of California consists of a Mediterranean climate, with sometimes excessive rainfall from October–April and nearly no rain the rest of the year. In the Pacific Northwest rain falls year-round, but is much heavier during winter and spring. The mountains of the west receive abundant precipitation and very heavy snowfall. The Cascades are one of the snowiest places in the world, with some places averaging over 600 inches (1,524 cm) of snow annually, but the lower elevations closer to the coast receive very little snow.

Questions and answers:
['
Q: What is the most prevalent type of climate nCalifornia?
A: Mediterranean', '
Q: During what time of the year does California receive the most rainfall?
A: October–April', '
Q: Which region of the US experiences rain year round?
A: Pacific Northwest', '
Q: Which region in the US is also one of the most snowiest places in the world?
A: The Cascades', '
Q: How many inches of snow do regions of the Cascades receive?
A: 600 inches']
On average, the mountains of the western states receive the highest levels of snowfall on Earth. The greatest annual snowfall level is at Mount Rainier in Washington, at 692 inches (1,758 cm); the record there was 1,122 inches (2,850 cm) in the winter of 1971–72. This record was broken by the Mt. Baker Ski Area in northwestern Washington which reported 1,140 inches (2,896 cm) of snowfall for the 1998-99 snowfall season. Other places with significant snowfall outside the Cascade Range are the Wasatch Mountains, near the Great Salt Lake, the San Juan Mountains in Colorado, and the Sierra Nevada, near Lake Tahoe.

Questions and answers:
['
Q: Which mountainous region receives the highest snowfall on Earth?
A: mountains of the western states', '
Q: Which mountain in Washington receives the most amount of snowfall?
A: Mount Rainier', '
Q: What is the record amount of snowfall at Mount Rainer?
A: 1,122 inches', '
Q: In what year did Mount Rainer receive a record amount of snowfall?
A: 1998-99', '
Q: The Sierra Nevadas are located near which lake?
A: Lake Tahoe']
In the east, while snowfall does not approach western levels, the region near the Great Lakes and the mountains of the Northeast receive the most. Along the northwestern Pacific coast, rainfall is greater than anywhere else in the continental U.S., with Quinault Rainforest in Washington having an average of 137 inches (348 cm). Hawaii receives even more, with 460 inches (1,168 cm) measured annually on Mount Waialeale, in Kauai. The Mojave Desert, in the southwest, is home to the driest locale in the U.S. Yuma, Arizona, has an average of 2.63 inches (6.7 cm) of precipitation each year.

Questions and answers:
['
Q: Which region of the US receives the most amount of rainfall?
A: northwestern Pacific coast', '
Q: What is the average amount of rainfall that the Quinault rainforest in Washington receives?
A: 137 inches', '
Q: Which regions in the East receives the most amount of snowfall?
A: Great Lakes and the mountains of the Northeast', '
Q: Which state receives an average of 460 inches of rainfall per year?
A: Hawaii', '
Q: What is the name of the desert that is located in the driest region in the US?
A: Mojave Desert']
In central portions of the U.S., tornadoes are more common than anywhere else on Earth and touch down most commonly in the spring and summer. Deadly and destructive hurricanes occur almost every year along the Atlantic seaboard and the Gulf of Mexico. The Appalachian region and the Midwest experience the worst floods, though virtually no area in the U.S. is immune to flooding. The Southwest has the worst droughts; one is thought to have lasted over 500 years and to have hurt Ancestral Pueblo peoples. The West is affected by large wildfires each year.

Questions and answers:
['
Q: Where are tornadoes most common on Earth?
A: central portions of the U.S.', '
Q: During which seasons are tornados most common?
A: spring and summer', '
Q: Which regions experience the worst flooding in the US?
A: Appalachian region and the Midwest', '
Q: Which region experiences the worst droughts in the US?
A: Southwest', '
Q: What type of disasters affects the western US every year?
A: wildfires']
Occasional severe flooding is experienced. There was the Great Mississippi Flood of 1927, the Great Flood of 1993, and widespread flooding and mudslides caused by the 1982-1983 El Niño event in the western United States. Localized flooding can, however, occur anywhere, and mudslides from heavy rain can cause problems in any mountainous area, particularly the Southwest. Large stretches of desert shrub in the west can fuel the spread of wildfires. The narrow canyons of many mountain areas in the west and severe thunderstorm activity during the summer lead to sometimes devastating flash floods as well, while Nor'Easter snowstorms can bring activity to a halt throughout the Northeast (although heavy snowstorms can occur almost anywhere).

Questions and answers:
['
Q: The Great Mississippi occurred during what year?
A: 1927', '
Q: What fuels wildfires and causes them to spread in the west?
A: desert shrub', "
Q: What type of storms can cause most activity to stop?
A: Nor'Easter snowstorms", '
Q: What is the name of the event that caused major flooding in the western US?
A: El Niño']
The West Coast of the continental United States and areas of Alaska (including the Aleutian Islands, the Alaskan Peninsula and southern Alaskan coast) make up part of the Pacific Ring of Fire, an area of heavy tectonic and volcanic activity that is the source of 90% of the world's earthquakes.[citation needed] The American Northwest sees the highest concentration of active volcanoes in the United States, in Washington, Oregon and northern California along the Cascade Mountains. There are several active volcanoes located in the islands of Hawaii, including Kilauea in ongoing eruption since 1983, but they do not typically adversely affect the inhabitants of the islands. There has not been a major life-threatening eruption on the Hawaiian islands since the 17th century. Volcanic eruptions can occasionally be devastating, such as in the 1980 eruption of Mount St. Helens in Washington.

Questions and answers:
['
Q: What is the area in the pacific known for heavy volcanic activity?
A: Pacific Ring of Fire', '
Q: Which Hawaiin volcano has been erupting since 1983?
A: Kilauea', '
Q: The Pacific Ring of Fire contains what percentage of the earthquakes on Earth?
A: 90%', '
Q: When was the last time that the Hawaiin islands experienced a life threatening volcanic eruption?
A: 17th century', '
Q: What year did Mt St. Helens erupt causing devastating damage?
A: 1980']
Compact Disc (CD) is a digital optical disc data storage format. The format was originally developed to store and play only sound recordings but was later adapted for storage of data (CD-ROM). Several other formats were further derived from these, including write-once audio and data storage (CD-R), rewritable media (CD-RW), Video Compact Disc (VCD), Super Video Compact Disc (SVCD), Photo CD, PictureCD, CD-i, and Enhanced Music CD. Audio CDs and audio CD players have been commercially available since October 1982.

Questions and answers:
['
Q: When did Audio CDs become available for purchase?
A: 1982', '
Q: What does CD stand for?
A: Compact Disc', '
Q: What does SVCD stand for?
A: Super Video Compact Disc', "
Q: What were CD's originally created to store?
A: sound recordings", '
Q: What does SVCD stand for?
A: Super Video Compact Disc', '
Q: In what year were compact discs realesed for purchase?
A: 1982', '
Q: What was the original intended format for CDs?
A: data storage']
In 2004, worldwide sales of audio CDs, CD-ROMs and CD-Rs reached about 30 billion discs. By 2007, 200 billion CDs had been sold worldwide. CDs are increasingly being replaced by other forms of digital storage and distribution, with the result that audio CD sales rates in the U.S. have dropped about 50% from their peak; however, they remain one of the primary distribution methods for the music industry. In 2014, revenues from digital music services matched those from physical format sales for the first time.

Questions and answers:
['
Q: In what year were digital and physical music sales the same?
A: 2014', '
Q: How many CDs had been distrubuted worldwide by 2007?
A: 200 billion', '
Q: In 2004 how many CDs had been sold around the world?
A: 2004', '
Q: What percent decrease did audio CD sales experience?
A: 50%', '
Q: What has caused a decrease in CD sales?
A: other forms of digital storage and distribution', '
Q: In 2004 how many CDs had been sold around the world?
A: 30 billion', '
Q: How many CDs had been distrubuted around the world by 2007?
A: 200 billion', '
Q: What has caused a decrease in CD sales?
A: other forms of digital storage']
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.

Questions and answers:
['
Q: Who created Compact Disc prototypes in the 1970s?
A: Philips and Sony', '
Q: How lond did the creation of Red Book CD-DA standard take?
A: a year', '
Q: To what does the compact disc owe its prosperity?
A: the cooperation between Philips and Sony', '
Q: How many CD players were sold in the United States in their first year?
A: 400,000', '
Q: What did the CD evolve from?
A: LaserDisc', '
Q: What made it possible for CDs to be played on any companies CD player?
A: unified design', '
Q: What year did CD players become available for purchase?
A: 1982', '
Q: To what does the compact disc owe its prosperity?
A: cooperation between Philips and Sony']
In 1974, L. Ottens, director of the audio division of Philips, started a small group with the aim to develop an analog optical audio disc with a diameter of 20 cm and a sound quality superior to that of the vinyl record. However, due to the unsatisfactory performance of the analog format, two Philips research engineers recommended a digital format in March 1974. In 1977, Philips then established a laboratory with the mission of creating a digital audio disc. The diameter of Philips's prototype compact disc was set at 11.5 cm, the diagonal of an audio cassette.

Questions and answers:
['
Q: In what year did Philips institute a laboratory to create a digital audio disc?
A: 1977', '
Q: What was the proposed diameter for the original compact disc?
A: 11.5 cm', '
Q: What year did Philips propse the idea of a digital audio format?
A: 1974', '
Q: Who was the director of the Philips audio division in 1974?
A: L. Ottens']
Heitaro Nakajima, who developed an early digital audio recorder within Japan's national public broadcasting organization NHK in 1970, became general manager of Sony's audio department in 1971. His team developed a digital PCM adaptor audio tape recorder using a Betamax video recorder in 1973. After this, in 1974 the leap to storing digital audio on an optical disc was easily made. Sony first publicly demonstrated an optical digital audio disc in September 1976. A year later, in September 1977, Sony showed the press a 30 cm disc that could play 60 minutes of digital audio (44,100 Hz sampling rate and 16-bit resolution) using MFM modulation. In September 1978, the company demonstrated an optical digital audio disc with a 150-minute playing time, 44,056 Hz sampling rate, 16-bit linear resolution, and cross-interleaved error correction code—specifications similar to those later settled upon for the standard Compact Disc format in 1980. Technical details of Sony's digital audio disc were presented during the 62nd AES Convention, held on 13–16 March 1979, in Brussels. Sony's AES technical paper was published on 1 March 1979. A week later, on 8 March, Philips publicly demonstrated a prototype of an optical digital audio disc at a press conference called "Philips Introduce Compact Disc" in Eindhoven, Netherlands.

Questions and answers:
['
Q: Where was the 62nd AES Convention held?
A: Brussels', "
Q: Who was the general manger of Sony's audio department in 1971?
A: Heitaro Nakajima", '
Q: What year did Sony first exhibit the use of an optical digital audio disc?
A: 1976', "
Q: What did Nakajima's team use to create a digital PCM adaptor audio tape recorder?
A: a Betamax video recorder", '
Q: Where was the Philips Introduce Compact disc conference held?
A: Eindhoven, Netherlands', "
Q: What did Nakajima's team use to create a digital PCM adaptor audio tape recorder?
A: Betamax video recorder", "
Q: When did Sony release it's AES technical paper?
A: 1 March 1979"]
As a result, in 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. Led by engineers Kees Schouhamer Immink and Toshitada Doi, the research pushed forward laser and optical disc technology. After a year of experimentation and discussion, the task force produced the Red Book CD-DA standard. First published in 1980, the standard was formally adopted by the IEC as an international standard in 1987, with various amendments becoming part of the standard in 1996.

Questions and answers:
['
Q: In what year did Sony and Philips band together to design a new digital audio disc?
A: 1979', '
Q: What year was the Red Book CD-DA standard released?
A: 1980', '
Q: When did the IEC isntigate the Red Book CD-DA as an international standard?
A: 1987', '
Q: Who headed the 1979 Sony and Philips digital audio disc task force?
A: Kees Schouhamer Immink and Toshitada Doi']
The Japanese launch was followed in March 1983 by the introduction of CD players and discs to Europe and North America (where CBS Records released sixteen titles). This event is often seen as the "Big Bang" of the digital audio revolution. The new audio disc was enthusiastically received, especially in the early-adopting classical music and audiophile communities, and its handling quality received particular praise. As the price of players gradually came down, and with the introduction of the portable Walkman the CD began to gain popularity in the larger popular and rock music markets. The first artist to sell a million copies on CD was Dire Straits, with their 1985 album Brothers in Arms. The first major artist to have his entire catalogue converted to CD was David Bowie, whose 15 studio albums were made available by RCA Records in February 1985, along with four greatest hits albums. In 1988, 400 million CDs were manufactured by 50 pressing plants around the world.

Questions and answers:
['
Q: Who first sold a million copies on CD?
A: Dire Straits', '
Q: Which artist was the first to have their full catalogue converted to CD?
A: David Bowie', '
Q: What year was the Dire Straits album Brothers in Arms released?
A: 1985', '
Q: How many studio albums did David Bowie release in February 1985?
A: 15', '
Q: How many CDs were mass produced in 1988?
A: 400 million', '
Q: How many studio albums did David Bowie release in February 1985?
A: 15']
The CD was planned to be the successor of the gramophone record for playing music, rather than primarily as a data storage medium. From its origins as a musical format, CDs have grown to encompass other applications. In 1983, following the CD's introduction, Immink and Braat presented the first experiments with erasable compact discs during the 73rd AES Convention. In June 1985, the computer-readable CD-ROM (read-only memory) and, in 1990, CD-Recordable were introduced, also developed by both Sony and Philips. Recordable CDs were a new alternative to tape for recording music and copying music albums without defects introduced in compression used in other digital recording methods. Other newer video formats such as DVD and Blu-ray use the same physical geometry as CD, and most DVD and Blu-ray players are backward compatible with audio CD.

Questions and answers:
['
Q: What does ROM stand for?
A: read-only memory', '
Q: What year did Sony and Philips release CD-Recordable?
A: 1990', '
Q: What was the original intended format for CDs?
A: musical format', '
Q: What year was the 73rd AES Convention?
A: 1983', '
Q: What was the CDs predecessor?
A: the gramophone record', '
Q: What was the CDs predecessor?
A: gramophone record']
Meanwhile, with the advent and popularity of Internet-based distribution of files in lossily-compressed audio formats such as MP3, sales of CDs began to decline in the 2000s. For example, between 2000 - 2008, despite overall growth in music sales and one anomalous year of increase, major-label CD sales declined overall by 20%, although independent and DIY music sales may be tracking better according to figures released 30 March 2009, and CDs still continue to sell greatly. As of 2012, CDs and DVDs made up only 34 percent of music sales in the United States. In Japan, however, over 80 percent of music was bought on CDs and other physical formats as of 2015.

Questions and answers:
['
Q: When did CD sales experience their original decline?
A: the 2000s', '
Q: What portion of music sales did CDs and DVDs account for in the United States as of 2012?
A: 34 percent', '
Q: Which country attributes over 80 percent of its music sales to physical formats?
A: Japan', '
Q: How are MP3s compressed?
A: lossily-compressed', '
Q: When did CD sales experience their original decline?
A: 2000s', '
Q: What has caused a decrease in CD sales?
A: Internet-based distribution of files']
Replicated CDs are mass-produced initially using a hydraulic press. Small granules of heated raw polycarbonate plastic are fed into the press. A screw forces the liquefied plastic into the mold cavity. The mold closes with a metal stamper in contact with the disc surface. The plastic is allowed to cool and harden. Once opened, the disc substrate is removed from the mold by a robotic arm, and a 15 mm diameter center hole (called a stacking ring) is created. The time it takes to "stamp" one CD is usually two to three seconds.

Questions and answers:
['
Q: How are CDs mass produced?
A: hydraulic press', '
Q: What type of material is used to make CDs?
A: raw polycarbonate plastic', '
Q: What size is the diameter of the center hole in a CD?
A: 15 mm', '
Q: How long does it take to stamp out one CD?
A: two to three seconds', '
Q: What is the term for the center hole in a CD?
A: stacking ring']
This method produces the clear plastic blank part of the disc. After a metallic reflecting layer (usually aluminium, but sometimes gold or other metal) is applied to the clear blank substrate, the disc goes under a UV light for curing and it is ready to go to press. To prepare to press a CD, a glass master is made, using a high-powered laser on a device similar to a CD writer. The glass master is a positive image of the desired CD surface (with the desired microscopic pits and lands). After testing, it is used to make a die by pressing it against a metal disc.

Questions and answers:
['
Q: What materials can be used to make the reflective layer on a CD?
A: usually aluminium, but sometimes gold or other metal', '
Q: What type of light is used to cure CDs?
A: UV', '
Q: What is a glass master?
A: positive image of the desired CD surface', '
Q: How are glass masters created?
A: high-powered laser']
The die is a negative image of the glass master: typically, several are made, depending on the number of pressing mills that are to make the CD. The die then goes into a press, and the physical image is transferred to the blank CD, leaving a final positive image on the disc. A small amount of lacquer is applied as a ring around the center of the disc, and rapid spinning spreads it evenly over the surface. Edge protection lacquer is applied before the disc is finished. The disc can then be printed and packed.

Questions and answers:
['
Q: What is the term for a negative image of the glass master?
A: die', '
Q: How is the positive image on a CD protected? 
A: lacquer', '
Q: How is lacquer distrubted on a CD?
A: rapid spinning']
The most expensive part of a CD is the jewel case. In 1995, material costs were 30 cents for the jewel case and 10 to 15 cents for the CD. Wholesale cost of CDs was $0.75 to $1.15, which retailed for $16.98. On average, the store received 35 percent of the retail price, the record company 27 percent, the artist 16 percent, the manufacturer 13 percent, and the distributor 9 percent. When 8-track tapes, cassette tapes, and CDs were introduced, each was marketed at a higher price than the format they succeeded, even though the cost to produce the media was reduced. This was done because the apparent value increased. This continued from vinyl to CDs but was broken when Apple marketed MP3s for $0.99, and albums for $9.99. The incremental cost, though, to produce an MP3 is very small.

Questions and answers:
['
Q: What is the priciest component of a CD?
A: jewel case', '
Q: Why did the cost of audio music increase when the production costs decreased?
A: value increased', '
Q: What did CDs retail for in 1995?
A: $16.98', '
Q: Who received the most profit from the sale of CDs?
A: the store', '
Q: How much did a jewel case cost in 1995?
A: 30 cents']
CD-R recordings are designed to be permanent. Over time, the dye's physical characteristics may change causing read errors and data loss until the reading device cannot recover with error correction methods. The design life is from 20 to 100 years, depending on the quality of the discs, the quality of the writing drive, and storage conditions. However, testing has demonstrated such degradation of some discs in as little as 18 months under normal storage conditions. This failure is known as disc rot, for which there are several, mostly environmental, reasons.

Questions and answers:
['
Q: How long are CDs expected to last?
A: 20 to 100 years', '
Q: What can cause sudden disc degradation?
A: disc rot', '
Q: Are CDs meant for permanent or temporary use?
A: permanent']
The ReWritable Audio CD is designed to be used in a consumer audio CD recorder, which will not (without modification) accept standard CD-RW discs. These consumer audio CD recorders use the Serial Copy Management System (SCMS), an early form of digital rights management (DRM), to conform to the United States' Audio Home Recording Act (AHRA). The ReWritable Audio CD is typically somewhat more expensive than CD-RW due to (a) lower volume and (b) a 3% AHRA royalty used to compensate the music industry for the making of a copy.

Questions and answers:
['
Q: What does SCMS stand for?
A: Serial Copy Management System', '
Q: What does DRM stand for?
A: digital rights management', '
Q: What does AHRA stand for?
A: Audio Home Recording Act', '
Q: What type of CD is intended to be used in a Consumer audio CD Recorder?
A: ReWritable Audio CD', '
Q: Which is less expensive, the ReWritable Audio CD or a CD-RW?
A: CD-RW']
Due to technical limitations, the original ReWritable CD could be written no faster than 4x speed. High Speed ReWritable CD has a different design, which permits writing at speeds ranging from 4x to 12x. Original CD-RW drives can only write to original ReWritable CDs. High Speed CD-RW drives can typically write to both original ReWritable CDs and High Speed ReWritable CDs. Both types of CD-RW discs can be read in most CD drives. Higher speed CD-RW discs, Ultra Speed (16x to 24x write speed) and Ultra Speed+ (32x write speed) are now available.

Questions and answers:
['
Q: How fast could the first ReWritable CD be written?
A: 4x speed', '
Q: Which CD has writing speeds betwen 4x and 12x?
A: High Speed ReWritable CD', '
Q: How fast can Ultra Speed+ CDs write?
A: 32x', '
Q: How fast can Ultra Speed CDs write?
A: 16x to 24x']