Ultimately, should a need exist to align a particular NTP era to the current calendar, the operating system in which NTP is embedded must provide the necessary high order bits, most conveniently from the file system or flash memory. With respect to the year 2000 issue, the most important thing to observe about the NTP time scale is that it knows nothing about days, years or centuries, only the seconds since the beginning of the latest era, the current one of which began on 1 January 1900. On 1 January 1970 when UNIX life began, the NTP time scale showed 2,208,988,800 and on 1 January 1972 when UTC life began, it showed 2,272,060,800. On the last second of year 1999, the NTP time scale will show 3,155,672,599 and one second later on the first second of the next century will show 3,155,672,600. Other than this observation, the NTP time scale has no knowledge of or provision for any of these eclectic seconds.
Time is a cultural construct whereby an event can be associated with a series of numbers.
For each of the following questions, decide whether the question is asking for the time interval between two events or the time at which an event occurred. Say it takes the Concorde two hours to fly from New York to London.