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).
The diaphragm is the main muscle used for breathing. The intercostal muscles are located between your ribs. They also play a major role in helping you breathe. Beneath your diaphragm are abdominal muscles. They help you breathe out when you're breathing fast (for example, during physical activity).