Breathing is then done through the tube, bypassing the mouth, nose, and throat. A tracheostomy is commonly referred to as a stoma. This is the name for the hole in the neck that the tube passes through.
A millimeter (mm) is the smallest. In order from smallest to largest they rank millimeter, centimeter (cm), decimeter (dm), and meter (m). These are all common units of length in the metric system.
In metric system, base unit of length is metre (meter is american spelling). Other common metric units of length are kilometer, centimeter and millimeter. In imperial and U.S. customary system, common length units are foot, inch, yard and mile.