QUES: Lie groups are of fundamental importance in modern physics: Noether's theorem links continuous symmetries to conserved quantities. Rotation, as well as translations in space and time are basic symmetries of the laws of mechanics. They can, for instance, be used to construct simple modelsimposing, say, axial symmetry on a situation will typically lead to significant simplification in the equations one needs to solve to provide a physical description.v["] Another example are the Lorentz transformations, which relate measurements of time and velocity of two observers in motion relative to each other. They can be deduced in a purely group-theoretical way, by expressing the transformations as a rotational symmetry of Minkowski space. The latter servesin the absence of significant gravitationas a model of space time in special relativity. The full symmetry group of Minkowski space, i.e. including translations, is known as the Poincare group. By the above, it plays a pivotal role in special relativity and, by implication, for quantum field theories. Symmetries that vary with location are central to the modern description of physical interactions with the help of gauge theory.
What are basic laws of mechanics?

ANS: unanswerable

QUES: Some rock musicians today use mandolins, often single-stringed electric models rather than double-stringed acoustic mandolins. One example is Tim Brennan of the Irish-American punk rock band Dropkick Murphys. In addition to electric guitar, bass, and drums, the band uses several instruments associated with traditional Celtic music, including mandolin, tin whistle, and Great Highland bagpipes. The band explains that these instruments accentuate the growling sound they favor. The 1991 R.E.M. hit "Losing My Religion" was driven by a few simple mandolin licks played by guitarist Peter Buck, who also played the mandolin in nearly a dozen other songs. The single peaked at No. 4 on the Billboard Hot 100 chart (#1 on the rock and alternative charts), Luther Dickinson of North Mississippi Allstars and The Black Crowes has made frequent use of the mandolin, most notably on the Black Crowes song "Locust Street." Armenian American rock group System of A Down makes extensive use of the mandolin on their 2005 double album Mezmerize/Hypnotize. Pop punk band Green Day has used a mandolin in several occasions, especially on their 2000 album, Warning. Boyd Tinsley, violin player of the Dave Matthews Band has been using an electric mandolin since 2005. Frontman Colin Meloy and guitarist Chris Funk of The Decemberists regularly employ the mandolin in the band's music. Nancy Wilson, rhythm guitarist of Heart, uses a mandolin in Heart's song "Dream of the Archer" from the album Little Queen, as well as in Heart's cover of Led Zeppelin's song "The Battle of Evermore." "Show Me Heaven" by Maria McKee, the theme song to the film Days of Thunder, prominently features a mandolin.
What type of mandolin do rock musicians today use?

ANS: single-stringed electric

QUES: The radish is also a typical food representing people of Nanjing, which has been spread through word of mouth as an interesting fact for many years in China. According to Nanjing.GOV.cn, "There is a long history of growing radish in Nanjing especially the southern suburb. In the spring, the radish tastes very juicy and sweet. It is well-known that people in Nanjing like eating radish. And the people are even addressed as 'Nanjing big radish', which means they are unsophisticated, passionate and conservative. From health perspective, eating radish can help to offset the stodgy food that people take during the Spring Festival".
What is considered to be a typical food for a Nanjing resident?

ANS: radish

QUES: Circadian rhythms allow organisms to anticipate and prepare for precise and regular environmental changes. They thus enable organisms to best capitalize on environmental resources (e.g. light and food) compared to those that cannot predict such availability. It has therefore been suggested that circadian rhythms put organisms at a selective advantage in evolutionary terms. However, rhythmicity appears to be as important in regulating and coordinating internal metabolic processes, as in coordinating with the environment. This is suggested by the maintenance (heritability) of circadian rhythms in fruit flies after several hundred generations in constant laboratory conditions, as well as in creatures in constant darkness in the wild, and by the experimental elimination of behavioral, but not physiological, circadian rhythms in quail.
By better using resources, how does that improve an organism's chances of surviving?

ANS:
selective advantage