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Author Question: A weightless spring is stretched 10 cm by a suspended 1-kg block. If two such springs are used to ... (Read 160 times) |
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.
Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.
All adults should have their cholesterol levels checked once every 5 years. During 2009–2010, 69.4% of Americans age 20 and older reported having their cholesterol checked within the last five years.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Throughout history, plants containing cardiac steroids have been used as heart drugs and as poisons (e.g., in arrows used in combat), emetics, and diuretics.