The amount of blood in an adult human is relatively constant: Around 4.7 litres, with of total weight of ~4.4 Kg (average density of blood: ~1.06). Perhaps slightly more (~5 litres?). And slightly less in women. So the percentage of total body weight varies, depending of total body weight. More information and details here: Volume of Blood in a Human
Social issue. A social issue is a problem that influences a considerable number of the individuals within a society. It is often the consequence of factors extending beyond an individual's social issue is the source of a conflicting opinion on the grounds of what is perceived as a morally just personal life or societal order. Social issues are distinguished from economic issues; however, some issues have both social and economic aspects. There are also issues that don't fall into either category, such as warf
Finally, there are cultural issues to consider and security challenges to address. It's an area that no company can ignore, says Forrester principal analyst Clay Richardson. Businesses Go Social. Social media has clearly arrived at the mainstream of enterprise IT.