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Author Question: U-235 and Pu-239 are both A) radioactive isotopes. B) fissionable isotopes. C) heavier than ... (Read 69 times) |
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.
Alzheimer's disease affects only about 10% of people older than 65 years of age. Most forms of decreased mental function and dementia are caused by disuse (letting the mind get lazy).
Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
Signs of depression include feeling sad most of the time for 2 weeks or longer; loss of interest in things normally enjoyed; lack of energy; sleep and appetite disturbances; weight changes; feelings of hopelessness, helplessness, or worthlessness; an inability to make decisions; and thoughts of death and suicide.