1 Intracellular fluid (2/3 of body water). 2  Per Guyton, in a body containing 40 litres of fluid, about 25 litres is intracellular, which amounts to 62.5% (5/8), close enough to the 2/3 rule of thumb. 3  Jackson's texts states 70% of body fluid is intracellular. 4  Extracellular fluid (1/3 of body water).
However, if you provided support to your brother, depending on the level of support and your brotherâs gross income for 2010, you may be able to claim him as a dependent on your tax return (under the qualifying relative rules).
Dependent Taxpayer Test â Qualifying Child. If you could be claimed as a dependent by another person, you cannot claim anyone else as a dependent. Even if you have a qualifying child or a qualifying relative, you cannot claim that person as a dependent. Your brother, sister, half brother, half sister, stepbrother, stepsister, or a descendant (for example, your niece or nephew) of any of them.