Context and question: In 1957, Braunstein further demonstrated that the rudimentary devices could be used for non-radio communication across a short distance. As noted by Kroemer Braunstein".. had set up a simple optical communications link: Music emerging from a record player was used via suitable electronics to modulate the forward current of a GaAs diode. The emitted light was detected by a PbS diode some distance away. This signal was fed into an audio amplifier, and played back by a loudspeaker. Intercepting the beam stopped the music. We had a great deal of fun playing with this setup." This setup presaged the use of LEDs for optical communication applications.
 What first device was needed to hear the signal from the initial GaAs diode?
Answer: unanswerable
Context and question: Like other digital music players, iPods can serve as external data storage devices. Storage capacity varies by model, ranging from 2 GB for the iPod Shuffle to 128 GB for the iPod Touch (previously 160 GB for the iPod Classic, which is now discontinued).
What's the storage capacity of the iPod Shuffle?
Answer: 2 GB
Context and question: Of the territories of Poland annexed by the Soviet Union between 1939 and 1940, the region around Białystok and a minor part of Galicia east of the San river around Przemyśl were returned to the Polish state at the end of World War II. Of all other territories annexed by the USSR in 1939–40, the ones detached from Finland (Karelia, Petsamo), Estonia (Ingrian area and Petseri County) and Latvia (Abrene) remained part of the Russian Federation, the successor state of the Soviet Union, after 1991. Northern Bukovina, Southern Bessarabia and Hertza remain part of Ukraine.
The regions of Białystok, Galicia and Przemyśl were returned to what country after world war II?
Answer:
Polish state