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One-color light is well suited for traffic lights and signals, exit signs, emergency vehicle lighting, ships' navigation lights or lanterns (chromacity and luminance standards being set under the Convention on the International Regulations for Preventing Collisions at Sea 1972, Annex I and the CIE) and LED-based Christmas lights. In cold climates, LED traffic lights may remain snow-covered. Red or yellow LEDs are used in indicator and alphanumeric displays in environments where night vision must be retained: aircraft cockpits, submarine and ship bridges, astronomy observatories, and in the field, e.g. night time animal watching and military field use.
What color LEDs are used when night vision is important?
A: Red or yellow

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The head is enclosed in a hard, heavily sclerotized, unsegmented, exoskeletal head capsule, or epicranium, which contains most of the sensing organs, including the antennae, ocellus or eyes, and the mouthparts. Of all the insect orders, Orthoptera displays the most features found in other insects, including the sutures and sclerites. Here, the vertex, or the apex (dorsal region), is situated between the compound eyes for insects with a hypognathous and opisthognathous head. In prognathous insects, the vertex is not found between the compound eyes, but rather, where the ocelli are normally. This is because the primary axis of the head is rotated 90 to become parallel to the primary axis of the body. In some species, this region is modified and assumes a different name.:13
What displays the most features on an insect?
A: Orthoptera

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As one of the earliest centers of book-printing in Europe (see above: History), Strasbourg for a long time held a large number of incunabuladocuments printed before 1500in her library as one of her most precious heritages. After the total destruction of this institution in 1870, however, a new collection had to be reassembled from scratch. Today, Strasbourg's different public and institutional libraries again display a sizable total number of incunabula, distributed as follows: Bibliotheque nationale et universitaire, ca. 2 098 Mediatheque de la ville et de la communaute urbaine de Strasbourg, 394 Bibliotheque du Grand Seminaire, 238 Mediatheque protestante, 94 and Bibliotheque alsatique du Credit Mutuel, 5.
When was the library destroyed?
A: 1870

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The town experienced major expansion during the Victorian era. The Southampton Docks company had been formed in 1835. In October 1838 the foundation stone of the docks was laid and the first dock opened in 1842. The structural and economic development of docks continued for the next few decades. The railway link to London was fully opened in May 1840. Southampton subsequently became known as The Gateway to the Empire.
What name did Southampton earn for its importance in creating a link to London?
A:
The Gateway to the Empire