kilogram - pound, metre - ?

YARD
List of words for the clue kilogram - pound, metre - ? from the crossword:
LITRE HECTARE GALLON ACRE UNIT METER TIME BEAT KILO MILE KILOMETRE INCH CENTEMETRE LITER EZRA STERE FOOT TONNES MASS
WordClue
ACREkilogram - pound, hectare - ?
INCHkilogram - pound, centemetre - ?
MASSsecond - time, kilogram - ?
MILEkilogram - pound, kilometre - ?
TIMEkilogram - mass, second - ?
UNITkilogram or hertz
LITREpound - kilogram, gallon - ?
METERmass - kilogram, distance - ?
METREpound - kilogram, yard - ?
POUNDmetre - yard, kilogram - ?
GALLONkilogram - pound, litre - ?
SECONDmass - kilogram, time - ?
HECTAREpound - kilogram, acre - ?
DISTANCEkilogram - mass, meter - ?
KILOGRAMyard - metre, pound - ?
STERLINGpound
KILOMETREpound - kilogram, mile - ?
CENTEMETREpound - kilogram, inch - ?
GALLONkilogram - pound, litre - ?
INCHkilometre - mile, centemetre - ?