"By what metric?" (3)
I believe the answer is:
how
(Other definitions for how that I've seen before include "See 16" , "Who (anag.)" , "In what manner or method?" , "In what way?" , "By what means?" .)
I believe the answer is:
how
(Other definitions for how that I've seen before include "See 16" , "Who (anag.)" , "In what manner or method?" , "In what way?" , "By what means?" .)