As altitude increases, the available amount of oxygen to sustain mental and physical alertness decreases with the overall air pressure, though the relative percentage of oxygen in air, at about 21%, remains practically unchanged up to 21,000 metres (70,000 ft).
  State legislators in Texas (both representatives and senators) make a salary of $7,200 per year.
How much does a one term US congressman make annually?   Congressmen and Senators make $174,000     Speaker of the House makes $223,500     Minority and Majority leaders in both houses make $193,400.