Effects as a function of altitude. The human body can perform best at sea level, where the atmospheric pressure is 101,325 Pa or 1013.25 millibars (or 1 atm, by definition). The concentration of oxygen (O2) in sea-level air is 20.9%, so the partial pressure of O2 (pO2) is 21.136 kPa.
On Tuesday, the New York-based carrier rolled out a new three-tier structure for fares, giving the cheapest fares to passengers without checked bags. The airline's new fare types are labeled Blue, Blue Plus and Blue Flex, according to notices posted on JetBlue.com. Price differences between the tiers will vary, but Blue fares generally will be $15 cheaper than Blue Plus, and Blue Flex will be about $85 higher than that, according to JetBlue.
Jetblue Airways Corporation Company Profile. JetBlue Airways is counting on more than low fares to make its ledgers jet-black. The carrier offers one-class service -- with leather seats, satellite TV from DIRECTV, satellite radio from XM, and movies -- to more than 32 million passengers a year, and taking them to more than 90 cities.