Rivastigmine (sold under the trade name Exelon) is a parasympathomimetic or cholinergic agent for the treatment of mild to moderate dementia of the Alzheimer's type and dementia due to Parkinson's disease.
Quick Answer. According to the University of Washington, cows sleep for approximately 3.9 hours per day, meaning that they spend about 16.9 percent of the day sleeping. Adult humans sleep for approximately 8 hours per day, which represents 33.3 percent of the day. Human infants sleep approximately 16 hours per day.
Given this much, we now know why we sleep. The average adult sleeps 7 to 8.6 hours a day. Children sleep more than adults; they spent about 10 hours a day sleeping. Newborns, however, may sleep for nearly two-thirds of their day. There is an age-related difference in average time spent sleeping. As a person ages, they require less sleep. The elderly only spent around 6.5 hours a day sleeping.