There are three principal layers; 1  External intercostal muscles aid in quiet and forced inhalation. They originate on ribs 1-11 and have their insertion on ribs 2-12. 2  Internal intercostal muscles aid in forced expiration (quiet expiration is a passive process).
Costs. A professional concrete contractor will typically charge $2-$4 per square foot for a simple stain application, including the sealer. A stain application with patterning and sawed lines will typically cost between $4 and $10 per square foot.
Polished Concrete Cost. Polished concrete pricing is basically dependent upon how many levels of grinding will be required to get the floor to a suitably smooth surface. The cost for polished concrete can go up from there depending upon any decorative effects that are applied such as staining or scoring, etc.his price is usually for commercial floors and includes staining or scoring the floors, according to John Buteyn of Colorado Hardscapes. $6-$12/ sq ft. The typical cost for polished concrete in a residential floor because it is more difficult to get a consistent look using a smaller machine, according to Buteyn.