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Anning, depicted with her dog. Mary Anning (21 May 1799 – 9 March 1847) was an English fossil collector and palaeontologist. She made discoveries of Jurassic marine fossil beds in the cliffs along the English Channel at Lyme Regis, which changed the scientific thinking about prehistoric life and the history of the Earth.
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. [9] It is mainly used as a eugeroic ( wakefulness promoter) or as a mild cognitive enhancer to increase alertness and attentional performance. [10] [11] Caffeine acts by blocking binding of adenosine to the adenosine A 1 receptor, which enhances release of the ...
Veganism is the practice of abstaining from the use of animal products—particularly in diet—and an associated philosophy that rejects the commodity status of animals.[c] A person who follows the diet or philosophy is known as a vegan. Distinctions may be made between several categories of veganism. Dietary vegans, also known as "strict ...
Planet Fitness, Inc. is an American franchisor and operator of fitness centers based in Hampton, New Hampshire.[4] The company has around 2,400 clubs,[2] making it one of the largest fitness club franchises by number of members and locations. The franchise has locations in the United States, Canada, Dominican Republic, Panama, Mexico, and ...
The number π (/paɪ/; spelled out as "pi") is a mathematical constant that is the ratio of a circle's circumference to its diameter, approximately equal to 3.14159. The number π appears in many formulae across mathematics and physics. It is an irrational number, meaning that it cannot be expressed exactly as a ratio of two integers, although ...
Current ISO 3166 country codes. The sortable table below contains the three sets of ISO 3166-1 country codes for each of its 249 countries, links to the ISO 3166-2 country subdivision codes, and the Internet country code top-level domains (ccTLD) which are based on the ISO 3166-1 alpha-2 standard with the few exceptions noted.
In probability theory and statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable. The general form of its probability density function is. The parameter is the mean or expectation of the distribution (and also its median and mode ), while the parameter is its ...
