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Author Question: A 10-kg block on a horizontal frictionless surface is attached to a light spring (force constant = ... (Read 2399 times) |
According to research, pregnant women tend to eat more if carrying a baby boy. Male fetuses may secrete a chemical that stimulates their mothers to step up her energy intake.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
Bisphosphonates were first developed in the nineteenth century. They were first investigated for use in disorders of bone metabolism in the 1960s. They are now used clinically for the treatment of osteoporosis, Paget's disease, bone metastasis, multiple myeloma, and other conditions that feature bone fragility.
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.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.