=+6. A study reported in the article “The Effects of Water Vapor Concentration on the Rate of Combustion of an Artificial Graphite in Humid Air Flow”

(Combustion and Flame, 1983: 107–118) gave data on x 5 temperature of a nitrogen–oxygen mixture (1000s of °F) under specified conditions and y 5 oxygen diffusivity. Summary quantities are n 5 9 ^ xi 5 12.6 ^ yi 5 27.68 ^ x 2 i 5 18.24 ^ xi yi 5 40.968 ^ y 2 i 5 93.3448