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TEXT F
First read the following question.
83. Gregorian calendar makes an error of ______ a year in time-measuring.
A. 126 seconds
B. 26 seconds
C. 52 seconds
D. 78 seconds
正确答案是
Now skim the passage and answer the question.
Devising accurate calendars and clocks to measure the flow of time has, through history, proved to be an elusive, protracted intellectual pursuit. Drawn to the movements of the heavens and the changing seasons, man developed the calendar. The Sumerians divided the year into 360 days, then designated 12 lunar months of 30 days each. The Egyptians extended the year by five days. Later changes by the Romans, plus refinements by Pope Gregory XIII in 1582, gave us today's Gregorian calendar, accurate to a day in every 3323 years.
Early societies also broke the day into smaller units, presumably for the same reason we do -- so we know when we're supposed to be somewhere. The sun, arching overhead daily, was undoubtedly the first timepiece, followed perhaps by the shadow of a stick stuck in the ground -- a crude sundial.