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2 天前 · Gross domestic product (GDP) is the market value of all final goods and services from a nation in a given year. [2] Countries are sorted by nominal GDP estimates from financial and statistical institutions, which are calculated at market or government official exchange rates. Nominal GDP does not take into account differences in the cost of ...
1 天前 · The UEFA Champions League (previously known as the European Cup, abbreviated as UCL, or sometimes, UEFA CL) is an annual club association football competition organised by the Union of European Football Associations (UEFA) and contested by top-division European clubs, deciding the competition winners through a round robin group stage to qualify ...
19 小時前 · By the time the Declaration of Independence was adopted in July 1776, the Thirteen Colonies and Great Britain had been at war for more than a year. Relations had been deteriorating between the colonies and the mother country since 1763. Parliament enacted a series of measures to increase revenue from the colonies, such as the Stamp Act of 1765 and the Townshend Acts of 1767.
2 天前 · The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BC. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as well as consonants.In Archaic and early Classical times, the Greek alphabet existed in many local variants, but, by the end of the 4th century BC, the ...
1 天前 · The electron ( e− , or β− in nuclear reactions) is a subatomic particle with a negative one elementary electric charge.[13] Electrons belong to the first generation of the lepton particle family,[14] and are generally thought to be elementary particles because they have no known components or substructure.[1] The electron's mass is ...
1 天前 · Basis of trigonometry: if two right triangles have equal acute angles, they are similar, so their corresponding side lengths are proportional. In mathematics, the trigonometric functions (also called circular functions, angle functions or goniometric functions) are real functions which relate an angle of a right-angled triangle to ratios of two side lengths.
2 天前 · 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 standard deviation.
