Apple MJLT2LL/A Manuale Proprietario

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Chapter 6    
Safety, handling, and support 
36
Understanding ergonomics
When you use the keyboard and trackpad, your shoulders should be relaxed. Your upper arm and 
forearm should form an angle that is slightly greater than a right angle, with your wrist and hand 
in roughly a straight line.
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This
Use a light touch when typing or using the trackpad and keep your hands and fingers relaxed. 
Avoid rolling your thumbs under your palms.
Not this
This
Change hand positions often to avoid fatigue. Some computer users might develop discomfort 
in their hands, wrists, or arms after intensive work without breaks. If you begin to develop 
chronic pain or discomfort in your hands, wrists, or arms, consult a qualified health specialist.
External mouse. If you use an external mouse, position the mouse at the same height as the 
keyboard and within a comfortable reach.
Chair. An adjustable chair that provides firm, comfortable support is best. Adjust the height of 
the chair so your thighs are horizontal and your feet are flat on the floor. The back of the chair 
should support your lower back (lumbar region). Follow the manufacturer’s instructions for 
adjusting the backrest to fit your body properly.
Built-in display. Adjust the angle of the display to minimize glare and reflections from overhead 
lights and windows. Do not force the display if you meet resistance. The display is not designed 
to open past 135 degrees.
You can adjust the brightness of the screen when you take the computer from one work location 
to another, or if the lighting in your work area changes.
For more information about ergonomics, see 
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Apple and the environment
At Apple, we recognize our responsibility to minimize the environmental impacts of our 
operations and products.
For information, go t
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