Your cells are surrounded by a very important type of lipid, called phospholipids. Phospholipids consist of a hydrophilic (or 'water loving') head and a hydrophobic (or 'water fearing') tail. Phospholipids like to line up and arrange themselves into two parallel layers, called a phospholipid bilayer. This layer makes up your cell membranes and is critical to a cell's ability to function.
On a film or modeling set, a makeup artist may spend six to eight hours doing makeup for the day. For an individual client appointment, the time span may be an hour to three hours. If a makeup artist is working for a bridal party, then he or she may spend the entire day working with clients.
Those 12-15 hours work best if you do 1 to 1.5 hours per day during your workweek, then 5-10 hours on the weekend. Few people are able to productively study for the GMAT for more than 2 hours or so at a sitting, so break up that time on weekends. Two 2-hour stretches, or perhaps three 1.5-hour sessions, is the way to go. How Many Weeks? Most of the major test-prep companies offer classes that take 6-8 weeks.