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1 dzień temu · A car, or an automobile, is a motor vehicle with wheels.Most definitions of cars state that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people over cargo.. The French inventor Nicolas-Joseph Cugnot built the first steam-powered road vehicle in 1769, while the Swiss inventor François Isaac de Rivaz designed and constructed the first internal ...
1 godzinę temu · The tiger (Panthera tigris) is a member of the genus Panthera and the largest living cat species native to Asia.It has a powerful, muscular body with a large head and paws, a long tail and orange fur with black, mostly vertical stripes. It is traditionally classified into nine recent subspecies, though some recognise only two subspecies, mainland Asian tigers and the island tigers of the Sunda ...
1 dzień temu · Properties Form and structure Gallium crystals Most metals are shiny and lustrous, at least when polished, or fractured. Sheets of metal thicker than a few micrometres appear opaque, but gold leaf transmits green light. This is due to the freely moving electrons which reflect light. Although most elemental metals have higher densities than nonmetals, there is a wide variation in their ...
1 dzień temu · Washing one's hands, a form of hygiene, is the most effective way to prevent the spread of infectious diseases. Hygiene is a set of practices performed to preserve health.According to the World Health Organization (WHO), "Hygiene refers to conditions and practices that help to maintain health and prevent the spread of diseases." Personal hygiene refers to maintaining the body's cleanliness.
1 dzień temu · A cross section of the shore-end of a modern submarine communications cable. 1 – Polyethylene 2 – Mylar tape 3 – Stranded steel wires 4 – Aluminium water barrier 5 – Polycarbonate 6 – Copper or aluminium tube 7 – Petroleum jelly 8 – Optical fibers Submarine cables are laid using special cable layer ships, such as the modern René Descartes [], operated by Orange Marine.
1 dzień temu · Archaic humans emerged out of Africa between 0.5 and 1.8 million years ago. This was followed by the emergence of anatomically modern humans (Homo sapiens) in East Africa around 300,000–250,000 years ago. The earliest known recorded history arose in Ancient Egypt, and later in Nubia, the Horn of Africa, the Maghreb and Ifrikiya, and the western Sahel. ...
1 dzień temu · The Royal Air Force (RAF) is the air and space force of the United Kingdom, British Overseas Territories and Crown Dependencies. It was formed towards the end of the First World War on 1 April 1918, becoming the second independent air force in the world after the Finnish Air Force (established 6 March 1918), by merging the Royal Flying Corps (RFC) and the Royal Naval Air Service (RNAS).
