Problem: Please answer a question about the following article about YouTube:
YouTube Red is YouTube's premium subscription service. It offers advertising-free streaming, access to exclusive content, background and offline video playback on mobile devices, and access to the Google Play Music "All Access" service. YouTube Red was originally announced on November 12, 2014, as "Music Key", a subscription music streaming service, and was intended to integrate with and replace the existing Google Play Music "All Access" service. On October 28, 2015, the service was re-launched as YouTube Red, offering ad-free streaming of all videos, as well as access to exclusive original content.
What service was "music key" intended to replace?
A: Google Play Music "All Access"
Problem: Please answer a question about the following article about Arena Football League:
In 2003, the season expanded to 16 games. There were also several rule changes in this period. In 2005, players were no longer allowed to run out of bounds. The only way for a player to go out of bounds presently is if he is tackled into or deliberately contacts the side boards. This was also the first year the ArenaBowl was played at a neutral site. In 2007, free substitution was allowed, ending the "iron man" era of one-platoon football. And in 2008, the "jack" linebacker was allowed to go sideboard to sideboard without being penalized for "illegal defense".
What year introduced the free substitution rule?
A: 2007
Problem: Please answer a question about the following article about Railway electrification system:
The first attempts to use standard-frequency single-phase AC were made in Hungary as far back as 1923, by the Hungarian Kalman Kando on the line between Budapest-Nyugati and Alag, using 16 kV at 50 Hz. The locomotives carried a four-pole rotating phase converter feeding a single traction motor of the polyphase induction type at 600 to 1,100 V. The number of poles on the 2,500 hp motor could be changed using slip rings to run at one of four synchronous speeds. The tests were a success so, from 1932 until the 1960s, trains on the Budapest-Hegyeshalom line (towards Vienna) regularly used the same system. A few decades after the Second World War, the 16 kV was changed to the Russian and later French 25 kV system.
What country has first tried to use single-phase AC?
A: Hungary
Problem: Please answer a question about the following article about Geological history of Earth:
The Carboniferous was a time of active mountain building, as the supercontinent Pangea came together. The southern continents remained tied together in the supercontinent Gondwana, which collided with North America-Europe (Laurussia) along the present line of eastern North America. This continental collision resulted in the Hercynian orogeny in Europe, and the Alleghenian orogeny in North America; it also extended the newly uplifted Appalachians southwestward as the Ouachita Mountains. In the same time frame, much of present eastern Eurasian plate welded itself to Europe along the line of the Ural mountains. There were two major oceans in the Carboniferous the Panthalassa and Paleo-Tethys. Other minor oceans were shrinking and eventually closed the Rheic Ocean (closed by the assembly of South and North America), the small, shallow Ural Ocean (which was closed by the collision of Baltica, and Siberia continents, creating the Ural Mountains) and Proto-Tethys Ocean.
Which two large oceans existed during the Carboniferous period?
A:
the Panthalassa and Paleo-Tethys