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Phase 1 Of The Second Avenue Subway
The Second Avenue Subway, a New York City Subway line that runs under Second Avenue on the East Side of Manhattan, has been proposed since 1920. The first phase of the line, consisting of three stations on the Upper East Side, started construction in 2007 and opened in 2017, ninety-seven years after the route was first proposed. Up until the 1960s, many distinct plans for the Second Avenue subway line were never carried out, though small segments were built in the 1970s as part of the Program for Action. The complex reasons for these delays are why the line is sometimes called "the line that time forgot". Work on the line started in 2007 following the development of a financially secure construction plan. The Metropolitan Transportation Authority (MTA) awarded a tunneling contract for the first phase of the project to the consortium of Schiavone/Shea/Skanska (S3) on March 20, 2007. This followed preliminary engineering and a final tunnel design completed by a joint venture bet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Second Avenue Subway Map Vc
The second (symbol: s) is a unit of time derived from the division of the day first into 24 hours, then to 60 minutes, and finally to 60 seconds each (24 × 60 × 60 = 86400). The current and formal definition in the International System of Units (SI) is more precise: The second ..is defined by taking the fixed numerical value of the caesium frequency, Δ''ν''Cs, the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be when expressed in the unit Hz, which is equal to s−1. This current definition was adopted in 1967 when it became feasible to define the second based on fundamental properties of nature with caesium clocks. As the speed of Earth's rotation varies and is slowing ever so slightly, a leap second is added at irregular intervals to civil time to keep clocks in sync with Earth's rotation. The definition that is based on of a rotation of the earth is still used by the Universal Time 1 (UT1) system. Etymology "Minute" comes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
