at a speed of one hundred kilometres per hour
11nebula — nebular, adj. /neb yeuh leuh/, n., pl. nebulae / lee , luy /, nebulas. 1. Astron. a. Also called diffuse nebula. a cloud of interstellar gas and dust. Cf. dark nebula, emission nebula, reflection nebula …
12rocket and missile system — ▪ weapons system Introduction any of a variety of weapons systems that deliver explosive warheads to their targets by means of rocket propulsion. Rocket is a general term used broadly to describe a variety of jet propelled missiles… …
13tunnels and underground excavations — ▪ engineering Introduction Great tunnels of the world Great tunnels of the worldhorizontal underground passageway produced by excavation or occasionally by nature s action in dissolving a soluble rock, such as limestone. A vertical opening …
14Cluj-Napoca — Cluj redirects here. For other uses, see Cluj (disambiguation). Coordinates: 46°46′N 23°35′E / 46.767°N 23.583°E / 46.767; 23.583 …
15Stockholm Metro — Stockholms tunnelbana Info Locale Stockholm Transit type Rapid transit …
16technology, history of — Introduction the development over time of systematic techniques for making and doing things. The term technology, a combination of the Greek technē, “art, craft,” with logos, “word, speech,” meant in Greece a discourse on the arts, both… …
17sand dune — Hill, mound, or ridge of windblown sand or other loose material such as clay particles. Dunes are commonly associated with desert regions and seacoasts, and there are large areas of dunes in nonglacial parts of Antarctica. * * * Introduction any …
18air-cushion machine — ▪ vehicle Introduction also called ground effect machine, or hovercraft, any of the machines characterized by movement in which a significant portion of the weight is supported by forces arising from air pressures developed around the… …
19North Australia Air War — North Australian Air War 1942–1943 Part of the Pacific Theater of World War II …
20Metrication — A speedometer used in American and British cars, showing the speed of the vehicle in miles per hour (outer, in white) and kilometres per hour (inner, in red) for Canadian[1] vehicles the locations are reversed …
