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The great Navicella mosaic (13051313) in the atrium of the Old St. Peter's is attributed to Giotto di Bondone. The giant mosaic, commissioned by Cardinal Jacopo Stefaneschi, was originally situated on the eastern porch of the old basilica and occupied the whole wall above the entrance arcade facing the courtyard. It depicted St. Peter walking on the waters. This extraordinary work was mainly destroyed during the construction of the new St. Peter's in the 17th century. Navicella means "little ship" referring to the large boat which dominated the scene, and whose sail, filled by the storm, loomed over the horizon. Such a natural representation of a seascape was known only from ancient works of art.
Navicella means what in Italian?
A: "little ship"

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Caesars Entertainment executives have been reconsidering the future of their three remaining Atlantic City properties (Bally's, Caesars and Harrah's), in the wake of a Chapter 11 bankruptcy filing by the company's casino operating unit in January 2015.
What year did Caesars Entertainment file for bankruptcy?
A: 2015

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A treaty is null and void if it is in violation of a peremptory norm. These norms, unlike other principles of customary law, are recognized as permitting no violations and so cannot be altered through treaty obligations. These are limited to such universally accepted prohibitions as those against the aggressive use of force, genocide and other crimes against humanity, piracy, hostilities directed at civilian population, racial discrimination and apartheid, slavery and torture, meaning that no state can legally assume an obligation to commit or permit such acts.
What type of norm is recognized as permitting no violations and so cannot be altered through treaty obligations?
A: peremptory norm

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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.
In what year were luminescence standards set?
A:
1972