The practical representative values of HETP for a number of commercial operations lies within a range of ______________ metre?
A. 0.1-0.2
B. 0.2-0.5
C. 0.4-0.9
D. 1.2-1.5
A. 0.1-0.2
B. 0.2-0.5
C. 0.4-0.9
D. 1.2-1.5