Here is a question about this article: Zinc is more reactive than iron or steel and thus will attract almost all local oxidation until it completely corrodes away. A protective surface layer of oxide and carbonate (Zn
5(OH)
6(CO
3)
2) forms as the zinc corrodes. This protection lasts even after the zinc layer is scratched but degrades through time as the zinc corrodes away. The zinc is applied electrochemically or as molten zinc by hot-dip galvanizing or spraying. Galvanization is used on chain-link fencing, guard rails, suspension bridges, lightposts, metal roofs, heat exchangers, and car bodies.
What is the answer to this question: What forms as zinc corrodes?
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So... protective surface layer of oxide and carbonate


Here is a question about this article: Stereophonic sound recording, which attempts to provide a more natural listening experience by reproducing the spatial locations of sound sources in the horizontal plane, was the natural extension to monophonic recording, and attracted various alternative engineering attempts. The ultimately dominant "45/45" stereophonic record system was invented by Alan Blumlein of EMI in 1931 and patented the same year. EMI cut the first stereo test discs using the system in 1933 (see Bell Labs Stereo Experiments of 1933) although the system was not exploited commercially until much later.
What is the answer to this question: When did EMI create the first stereo discs?
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So... 1933


Here is a question about this article: Igor returned to Kiev keen for revenge. He assembled a large force of warriors from among neighboring Slavs and Pecheneg allies, and sent for reinforcements of Varangians from “beyond the sea.” In 944 the Rus' force advanced again on the Greeks, by land and sea, and a Byzantine force from Cherson responded. The Emperor sent gifts and offered tribute in lieu of war, and the Rus' accepted. Envoys were sent between the Rus’, the Byzantines, and the Bulgarians in 945, and a peace treaty was completed. The agreement again focused on trade, but this time with terms less favorable to the Rus’, including stringent regulations on the conduct of Rus’ merchants in Cherson and Constantinople and specific punishments for violations of the law. The Byzantines may have been motivated to enter the treaty out of concern of a prolonged alliance of the Rus', Pechenegs, and Bulgarians against them, though the more favorable terms further suggest a shift in power.
What is the answer to this question: Where did Igor get warriors from after returning to Kiev after being drivin out by the Byzatines?
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So...
Slavs and Pecheneg allies