The problem: Answer a question about this article:
The space-consuming analog video signal of a LaserDisc limited playback duration to 30 minutes (CAV) or 60 minutes (CLV) per side because of the hardware manufacturer's refusal to reduce line count for increased playtime. After one side was finished playing, a disc has to be flipped over in order to continue watching a movie, and some titles fill two or more discs. Many players, especially units built after the mid-1980s, can "flip" discs automatically by rotating the optical pickup to the other side of the disc, but this is accompanied by a pause in the movie during the side change. If the movie is longer than what could be stored on two sides of a single disc, manually swapping to a second disc is necessary at some point during the film. One exception to this rule is the Pioneer LD-W1, which features two disc platters. In addition, perfect still frames and random access to individual still frames is limited only to the more expensive CAV discs, which only had a playing time of approximately 30 minutes per side. In later years, Pioneer and other manufacturers overcame this limitation by incorporating a digital memory buffer, which "grabbed" a single frame from a CLV disc.
Which format allows for more playback tie per side, CLV or CAV?
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The answer: CLV


The problem: Answer a question about this article:
As a member of the European Union, Estonia is considered a high-income economy by the World Bank. The GDP (PPP) per capita of the country, a good indicator of wealth, was in 2015 $28,781 according to the IMF, between that of Slovak Republic and Lithuania, but below that of other long-time EU members such as Italy or Spain. The country is ranked 8th in the 2015 Index of Economic Freedom, and the 4th freest economy in Europe. Because of its rapid growth, Estonia has often been described as a Baltic Tiger beside Lithuania and Latvia. Beginning 1 January 2011, Estonia adopted the euro and became the 17th eurozone member state.
What countries share similar levels of GDP with Estonia?
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The answer: Slovak Republic and Lithuania


The problem: Answer a question about this article:
Nanjing, with a total land area of 6,598 square kilometres (2,548 sq mi), is situated in the heartland of drainage area of lower reaches of Yangtze River, and in Yangtze River Delta, one of the largest economic zones of China. The Yangtze River flows past the west side and then north side of Nanjing City, while the Ningzheng Ridge surrounds the north, east and south side of the city. The city is 300 kilometres (190 mi) west-northwest of Shanghai, 1,200 kilometres (750 mi) south-southeast of Beijing, and 1,400 kilometres (870 mi) east-northeast of Chongqing. The downstream Yangtze River flows from Jiujiang, Jiangxi, through Anhui and Jiangsu to East Sea, north to drainage basin of downstream Yangtze is Huai River basin and south to it is Zhe River basin, and they are connected by the Grand Canal east to Nanjing. The area around Nanjing is called Hsiajiang (下江, Downstream River) region, with Jianghuai (江淮) stressing northern part and Jiangzhe (江浙) stressing southern part. The region is also known as Dongnan (東南, South East, the Southeast) and Jiangnan (江南, River South, south of Yangtze).
How large is Nanjing, in miles?
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The answer: 2,548 sq mi


The problem: Answer a question about this article:
The radiation pattern and even the driving point impedance of an antenna can be influenced by the dielectric constant and especially conductivity of nearby objects. For a terrestrial antenna, the ground is usually one such object of importance. The antenna's height above the ground, as well as the electrical properties (permittivity and conductivity) of the ground, can then be important. Also, in the particular case of a monopole antenna, the ground (or an artificial ground plane) serves as the return connection for the antenna current thus having an additional effect, particularly on the impedance seen by the feed line.
Whats another name for the ground?
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The answer:
artificial ground plane