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Author Question: During most of its history, Europe was in Stage 1 of the demographic transition. Indicate whether ... (Read 71 times) |
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.
There used to be a metric calendar, as well as metric clocks. The metric calendar, or "French Republican Calendar" divided the year into 12 months, but each month was divided into three 10-day weeks. Each day had 10 decimal hours. Each hour had 100 decimal minutes. Due to lack of popularity, the metric clocks and calendars were ended in 1795, three years after they had been first marketed.