Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Salts of many oxidation states of uranium are water-soluble and may be studied in aqueous solutions. The most common ionic forms are U3+ (brown-red), U4+ (green), UO+
2 (unstable), and UO2+
2 (yellow), for U(III), U(IV), U(V), and U(VI), respectively. A few solid and semi-metallic compounds such as UO and US exist for the formal oxidation state uranium(II), but no simple ions are known to exist in solution for that state. Ions of U3+ liberate hydrogen from water and are therefore considered to be highly unstable. The UO2+
2 ion represents the uranium(VI) state and is known to form compounds such as uranyl carbonate, uranyl chloride and uranyl sulfate. UO2+
2 also forms complexes with various organic chelating agents, the most commonly encountered of which is uranyl acetate.
What common complex is formed by the UO2+ 2 ion with organic chelating agents?
A: uranyl acetate

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Many Sanskrit loanwords are also found in Austronesian languages, such as Javanese, particularly the older form in which nearly half the vocabulary is borrowed. Other Austronesian languages, such as traditional Malay and modern Indonesian, also derive much of their vocabulary from Sanskrit, albeit to a lesser extent, with a larger proportion derived from Arabic. Similarly, Philippine languages such as Tagalog have some Sanskrit loanwords, although more are derived from Spanish. A Sanskrit loanword encountered in many Southeast Asian languages is the word bhasa, or spoken language, which is used to refer to the names of many languages.
Tagalog is what kind of language?
A: Philippine

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Network effects are a large factor with electrification. When converting lines to electric, the connections with other lines must be considered. Some electrifications have subsequently been removed because of the through traffic to non-electrified lines. If through traffic is to have any benefit, time consuming engine switches must occur to make such connections or expensive dual mode engines must be used. This is mostly an issue for long distance trips, but many lines come to be dominated by through traffic from long-haul freight trains (usually running coal, ore, or containers to or from ports). In theory, these trains could enjoy dramatic savings through electrification, but it can be too costly to extend electrification to isolated areas, and unless an entire network is electrified, companies often find that they need to continue use of diesel trains even if sections are electrified. The increasing demand for container traffic which is more efficient when utilizing the double-stack car also has network effect issues with existing electrifications due to insufficient clearance of overhead electrical lines for these trains, but electrification can be built or modified to have sufficient clearance, at additional cost.
What does the increasing demand for container traffic make companies use more often?
A: diesel trains

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The history of biodiversity during the Phanerozoic (the last 540 million years), starts with rapid growth during the Cambrian explosiona period during which nearly every phylum of multicellular organisms first appeared. Over the next 400 million years or so, invertebrate diversity showed little overall trend, and vertebrate diversity shows an overall exponential trend. This dramatic rise in diversity was marked by periodic, massive losses of diversity classified as mass extinction events. A significant loss occurred when rainforests collapsed in the carboniferous. The worst was the Permian-Triassic extinction event, 251 million years ago. Vertebrates took 30 million years to recover from this event.
In which event did the vertebrates collapse in the carboniferous?
A:
unanswerable