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.
  $10,000 a year. But they make about $30,000 a year on average because they put themselves on about 7 to 8 committees. This way they get committee meeting pay to get arou â¦ nd the low salary. The least amount that any one state senator made this year was about $21,000, the most was about $48,000.