You can elect to use a 52-53-week tax year if you keep your books and records and report your income and expenses on that basis. If you make this election, your 52-53-week tax year must always end on the same day of the week.
Forced Inhalation. Involved in the mechanics of breathing; The muscles involved in this type of breathing are the diaphragm, the external intercostal muscles, and the accessory respiratory muscles (activated when respiration increases significantly).
Anatomy and physiology of muscles involved in breathing. The breathing pump muscles are a complex arrangement that form a semirigid bellows around the lungs. Essentially, all muscles that attach to the rib cage have the potential to generate a breathing action, but the principal muscles are shown in figure 1.7.