英语翻译
Simpy calculating the lepgths of time necessary to double the world's population is instructive.impressively,the time required grows ever shorter:6000 years before christ,1 000 000 years were necessary to doube the population,then about 1650 years after Christ only 1000around the 1850's 200 years,in 1930 80 years.currently,the world's population doubles every 37 years.
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