I will assume that this question is about scientific notation (also assuming that the first number is 3.4*10^2), where you can arrange the numbers by the exponent of the 10, so from least to greatest:
[tex]8.11*10^{-3} [/tex], [tex]3.4*10^{2} [/tex], 435, and [tex]1.2*10^{7} [/tex]
