When the pressure around the chest wall returns to that of the surrounding air, expiration occurs passively owing to the elastic recoil of the lungs and chest wall. However, during the poliomyelitis epidemic mortality decreased from 87% to 40% when INPV was replaced by positive-pressure ventilation.
Part-Time Per-Credit Costs. The per-credit-hour charge for part-time undergraduate students at Wilmington University in 2015 - 2016 was $346. Typically, college classes consist of 3 or 4 credits, bringing the cost per class to $1,038 or $1,384. At many colleges, full-time tuition kicks in at around 12 credit hours.
Part-Time Per-Credit Costs. 832 of the 10,440 undergrads at College of Charleston take classes part-time. College of Charleston's fee per credit hour for part-time undergraduate students residing outside the State of South Carolina was $1,185 per credit in the 2015 - 2016 school year. College of Charleston offers a 61.7% discount for in-state (South Carolina) students.