A semiconductor has equal electron and hole concentration of `6xx10^(8)//m^(3)`. On doping with certain impurity, electron concentration increases to `9xx10^(12)//m^(3)`. (i) Identify the new semiconductor obtained after doping. (ii) Calculate the new hole concentration. (iii) How does the energy gap vary with doping?
A. `2xx10^4` per `m^3`
B. `2xx10^2` per `m^3`
C. `4xx10^4` per `m^3`
D. `4xx10^2` per `m^3`