Apple MB535LL User Guide - Page 81

 Position the mouse at the same height as your keyboard. Allow adequate space to use the mouse comfortably.  Arrange the display so that the top of the screen is slightly below eye level when you're sitting at the keyboard. The best distance from your eyes to the screen is up to you, although most people seem to prefer 18 to 28 inches (45 to 70 cm).  Position the display to minimize glare and reflections on the screen from overhead lights and nearby windows. If possible, use a tiltable display stand. The stand lets you set the display at the best angle for viewing, helping to reduce or eliminate glare from lighting sources you can't move. Shoulders relaxed Forearms and hands in a straight line 45-70 cm (18-28 in.) Top of the screen at or slightly below eye level (You may need to adjust the height of your display by raising or lowering your work surface.) Forearms level or tilted slightly Screen positioned to avoid reflected glare Lower back supported Clearance under work surface Thighs tilted slightly Feet flat on the floor or on a footrest Appendix B Safety, Maintenance, and Ergonomics 81