现测量了AB和CD两段距离，得DAB=125.34m，DBA=125.29m，DCD=236.56m，DDC=236.61m，求哪段距离测量的精度高?

D`AB=1/2(125.29+125.34)=125.32mDCD`=1/2(236.56+236.61)=236.59mKAB=(│D│/DAB)=(│125.34-125.29│/125.32)=(0.05/125.32)=(1/2506)KCD=(│236.56-236.61│/236.59)=(0.05/236.59)=(1/4732)KABKCDAB段精度高。