Problem: Thuringia:

Environmental damage in Thuringia has been reduced to a large extent after 1990. The condition of forests, rivers and air was improved by modernizing factories, houses (decline of coal heating) and cars, and contaminated areas such as the former Uranium surface mines around Ronneburg have been remediated. Today's environmental problems are the salination of the Werra river, caused by discharges of K+S salt mines around Unterbreizbach and overfertilisation in agriculture, damaging the soil and small rivers.

What are today's small environmental problems?
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A: unanswerable


Problem: Light-emitting diode:

There are several types of multi-color white LEDs: di-, tri-, and tetrachromatic white LEDs. Several key factors that play among these different methods, include color stability, color rendering capability, and luminous efficacy. Often, higher efficiency will mean lower color rendering, presenting a trade-off between the luminous efficacy and color rendering. For example, the dichromatic white LEDs have the best luminous efficacy (120 lm/W), but the lowest color rendering capability. However, although tetrachromatic white LEDs have excellent color rendering capability, they often have poor luminous efficacy. Trichromatic white LEDs are in between, having both good luminous efficacy (>70 lm/W) and fair color rendering capability.

 Higher efficiency in multi-color white LEDs don't mean what?
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A: unanswerable


Problem: British Isles:

The earliest known use of the phrase Brytish Iles in the English language is dated 1577 in a work by John Dee. Today, this name is seen by some as carrying imperialist overtones although it is still commonly used. Other names used to describe the islands include the Anglo-Celtic Isles, Atlantic archipelago, British-Irish Isles, Britain and Ireland, UK and Ireland, and British Isles and Ireland. Owing to political and national associations with the word British, the Government of Ireland does not use the term British Isles and in documents drawn up jointly between the British and Irish governments, the archipelago is referred to simply as "these islands". Nonetheless, British Isles is still the most widely accepted term for the archipelago.

What term is not used by the UK?
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A: unanswerable


Problem: Pesticide:

In 2006 and 2007, the world used approximately 2.4 megatonnes (5.3×109 lb) of pesticides, with herbicides constituting the biggest part of the world pesticide use at 40%, followed by insecticides (17%) and fungicides (10%). In 2006 and 2007 the U.S. used approximately 0.5 megatonnes (1.1×109 lb) of pesticides, accounting for 22% of the world total, including 857 million pounds (389 kt) of conventional pesticides, which are used in the agricultural sector (80% of conventional pesticide use) as well as the industrial, commercial, governmental and home & garden sectors.Pesticides are also found in majority of U.S. households with 78 million out of the 105.5 million households indicating that they use some form of pesticide. As of 2007, there were more than 1,055 active ingredients registered as pesticides, which yield over 20,000 pesticide products that are marketed in the United States.

What amount of conventional pesticide use does the agricultural sector account for?
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A:
80%