A collapsed lung, also known as a pneumothorax, occurs when air escapes out of a lung and becomes trapped inside the space between the chest and lung cavities. This can be caused by air blisters in the lungs that break open, sudden air pressure changes, or trauma to the chest or ribcage.
The IRS interpreted this provision as applying only to full-time students. In a 1993 technical advice memorandum, the IRS provided a safe-harbor definition of a full-time undergraduate student as one who is taking 12 credit hours and working no more than 20 hours per week.
An adult learner (North America) or mature learner (UK) (sometimes also called adult student, returning adult, adult returner, and student) is a person who is 18 years and up who is involved in forms of learning.dult learners are considered distinct from child learners due primarily to the work of Malcolm Knowles, who developed the principle of Andragogy.