Using the information given in Table 10.4, determine the ratio of local pressure and density to sea-level values. Estimate the value of air density at the cruising altitude of most commercial airliners.

  

      

  

      

P Altitude (m) Psea level sea level 0 (sea level) 1000 3000 5000 8000 10,000 12,000 14,000 15,000