Problem: Antenna (radio):

It is best for the receiving antenna to match the polarization of the transmitted wave for optimum reception. Intermediate matchings will lose some signal strength, but not as much as a complete mismatch. A circularly polarized antenna can be used to equally well match vertical or horizontal linear polarizations. Transmission from a circularly polarized antenna received by a linearly polarized antenna (or vice versa) entails a 3 dB reduction in signal-to-noise ratio as the received power has thereby been cut in half.

A transmission can cause reduction in what?
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A: signal-to-noise ratio

Problem: The Valencia Metro derailment occurred on 3 July 2006 at 1 pm. CEST (1100 UTC) between Jesus and Placa d'Espanya stations on Line 1 of the Metrovalencia mass transit system. 43 people were killed and more than ten were seriously injured. It was not immediately clear what caused the crash. Both the Valencian government spokesman Vicente Rambla and Mayor Rita Barbera called the accident a "fortuitous" event. However, the trade union CC.OO. accused the authorities of "rushing" to say anything but admit that Line 1 is in a state of "constant deterioration" with a "failure to carry out maintenance".
How many people were gravely injured by the derailment?
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Answer: more than ten

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Cordwood construction can save significant space and was often used with wire-ended components in applications where space was at a premium (such as missile guidance and telemetry systems) and in high-speed computers, where short traces were important. In cordwood construction, axial-leaded components were mounted between two parallel planes. The components were either soldered together with jumper wire, or they were connected to other components by thin nickel ribbon welded at right angles onto the component leads. To avoid shorting together different interconnection layers, thin insulating cards were placed between them. Perforations or holes in the cards allowed component leads to project through to the next interconnection layer. One disadvantage of this system was that special nickel-leaded components had to be used to allow the interconnecting welds to be made. Differential thermal expansion of the component could put pressure on the leads of the components and the PCB traces and cause physical damage (as was seen in several modules on the Apollo program). Additionally, components located in the interior are difficult to replace. Some versions of cordwood construction used soldered single-sided PCBs as the interconnection method (as pictured), allowing the use of normal-leaded components.
What gets mounted in the middle of two parallel planes in a cordwood construction?
A: axial-leaded components

Context and question: Columbia founded Epic Records in 1953. In 1956, Conkling left Columbia, he would help establish the National Academy of Recording Arts and Sciences before eventually becoming the first president of the newly launched Warner Bros. Records, and Goddard Lieberson began the first of two stints as head of the record company. In 1958, Columbia founded another label, Date Records, which initially issued rockabilly music.
Epic Records founded Columbia in what year?
Answer: unanswerable

Question: Baptists have faced many controversies in their 400-year history, controversies of the level of crises. Baptist historian Walter Shurden says the word "crisis" comes from the Greek word meaning "to decide." Shurden writes that contrary to the presumed negative view of crises, some controversies that reach a crisis level may actually be "positive and highly productive." He claims that even schism, though never ideal, has often produced positive results. In his opinion crises among Baptists each have become decision-moments that shaped their future. Some controversies that have shaped Baptists include the "missions crisis", the "slavery crisis", the "landmark crisis", and the "modernist crisis".
Is there an answer to this question: What did Shurden claim was never ideal, has often produced positive results?

Answer: controversies that have shaped Baptists

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
European colonialism in the Sahara began in the 19th century. France conquered the regency of Algiers from the Ottomans in 1830, and French rule spread south from Algeria and eastwards from Senegal into the upper Niger to include present-day Algeria, Chad, Mali then French Sudan including Timbuktu, Mauritania, Morocco (1912), Niger, and Tunisia (1881). By the beginning of the 20th century, the trans-Saharan trade had clearly declined because goods were moved through more modern and efficient means, such as airplanes, rather than across the desert.
When did France relinquish control of Morocco?
A:
unanswerable