Alpine crystals have been studied and collected for hundreds of years, and began to be classified in the 18th century. Leonhard Euler studied the shapes of crystals, and by the 19th century crystal hunting was common in Alpine regions. David Friedrich Wiser amassed a collection of 8000 crystals that he studied and documented. In the 20th century Robert Parker wrote a well-known work about the rock crystals of the Swiss Alps; at the same period a commission was established to control and standardize the naming of Alpine minerals.
When did the alpine crystals begin to be classified? 
the 18th century


Input: Valencia
Valencia (/vəˈlɛnsiə/; Spanish: [baˈlenθja]), or València (Valencian: [vaˈlensia]), is the capital of the autonomous community of Valencia and the third largest city in Spain after Madrid and Barcelona, with around 800,000 inhabitants in the administrative centre. Its urban area extends beyond the administrative city limits with a population of around 1.5 million people. Valencia is Spain's third largest metropolitan area, with a population ranging from 1.7 to 2.5 million. The city has global city status. The Port of Valencia is the 5th busiest container port in Europe and the busiest container port on the Mediterranean Sea.

What body of water is Valencia located on?
Output: the Mediterranean Sea


Input: Article: Many species of the second major avialan lineage to diversify, the Euornithes (meaning "true birds", because they include the ancestors of modern birds), were semi-aquatic and specialized in eating fish and other small aquatic organisms. Unlike the enantiornithes, which dominated land-based and arboreal habitats, most early euornithes lacked perching adaptations and seem to have included shorebird-like species, waders, and swimming and diving species. The later included the superficially gull-like Ichthyornis, the Hesperornithiformes, which became so well adapted to hunting fish in marine environments that they lost the ability to fly and became primarily aquatic. The early euornithes also saw the development of many traits associated with modern birds, like strongly keeled breastbones, toothless, beaked portions of their jaws (though most non-avian euornithes retained teeth in other parts of the jaws). Euornithes also included the first avialans to develop true pygostyle and a fully mobile fan of tail feathers, which may have replaced the "hind wing" as the primary mode of aerial maneuverability and braking in flight.

Now answer this question: What group became the first avialans to develop true pygostyle and a fully mobile fan of tail feathers?

Output: Euornithes


Article: In spite of their flaws, such as the lack of portability, records still have enthusiastic supporters. Vinyl records continue to be manufactured and sold today, especially by independent rock bands and labels, although record sales are considered to be a niche market composed of audiophiles, collectors, and DJs. Old records and out-of-print recordings in particular are in much demand by collectors the world over. (See Record collecting.) Many popular new albums are given releases on vinyl records and older albums are also given reissues, sometimes on audiophile-grade vinyl.

Question: Are records generally out of print as of date?
Ans: Vinyl records continue to be manufactured and sold today


Here is a question about this article: According to reciprocity, the efficiency of an antenna used as a receiving antenna is identical to the efficiency as defined above. The power that an antenna will deliver to a receiver (with a proper impedance match) is reduced by the same amount. In some receiving applications, the very inefficient antennas may have little impact on performance. At low frequencies, for example, atmospheric or man-made noise can mask antenna inefficiency. For example, CCIR Rep. 258-3 indicates man-made noise in a residential setting at 40 MHz is about 28 dB above the thermal noise floor. Consequently, an antenna with a 20 dB loss (due to inefficiency) would have little impact on system noise performance. The loss within the antenna will affect the intended signal and the noise/interference identically, leading to no reduction in signal to noise ratio (SNR).
What is the answer to this question: In what type of programs would low efficiency antennas not make a difference in effectiveness?
****
So... receiving


Article: On March 30, 2015, it was announced that Beyoncé is a co-owner, with various other music artists, in the music streaming service Tidal. The service specialises in lossless audio and high definition music videos. Beyoncé's husband Jay Z acquired the parent company of Tidal, Aspiro, in the first quarter of 2015. Including Beyoncé and Jay-Z, sixteen artist stakeholders (such as Kanye West, Rihanna, Madonna, Chris Martin, Nicki Minaj and more) co-own Tidal, with the majority owning a 3% equity stake. The idea of having an all artist owned streaming service was created by those involved to adapt to the increased demand for streaming within the current music industry, and to rival other streaming services such as Spotify, which have been criticised for their low payout of royalties. "The challenge is to get everyone to respect music again, to recognize its value", stated Jay-Z on the release of Tidal.

Question: What music service is accused of providing low royalty amounts?
Ans:
Spotify