context1: The Northern California Association to Preserve Bodega Head (NCAPBH) was involved in the controversy over the proposed Bodega Bay Nuclear Power Plant in the early 1960s. In June 1963, NCAPBH organized a public meeting and 1,500 helium balloons were released into the <strong>air</strong>. They carried the message This balloon could represent a radioactive <strong>molecule</strong> of strontium 90 or iodine 131.
context2: The RMS velocities of diatomic nitrogen and oxygen are very similar and thus no change occurs in the ratio of oxygen to nitrogen. However, it is the <strong>air</strong> pressure itself, the number of <strong>molecules</strong> (of both oxygen and nitrogen) per given volume, which drops as altitude increases. Consequently, the available amount of oxygen to sustain mental and physical alertness decreases above.