長度單位：km,m,dm,cm,mm,μm,nm1km=m=mm=μm=nm1m=mm=μm=nm1nm=μm=mm=m1m=dm=cm=mm1mm=cm=dm=m1m=km1cm=m1dm=m1μm=m1cm=km170cm=m8dm=m0.005m=m36m=km760mm=cm48km=m54km=m面積單位：m2，dm2，cm2，mm21m2=dm21m2=mm21m2=cm21cm2=m21dm2=m21mm2=m2100cm2=m28000cm2=m2500cm2=m260cm2=m29cm2=m27.5cm2=m238mm2=m296dm2=m2625cm2=m245cm2=m2體積單位：m3，dm3，cm3，L,ml1L=ml1ml=L1L=dm31ml=cm31m3=dm31m3=cm31dm3=cm31cm3=dm31cm3=m360cm3=m3400cm3=m318cm3=m3質(zhì)量單位：t，kg，g，mg1t=kg1kg=g1g=mg1g=kg1kg=t50t=kg650kg=t13g=kg480g=kg8t=kg5400kg=t1500g=kg時間單位：h，min，s1h=min1min=s1h=s0.5h=min45min=h30min=h23h=min13h=6min=s10min=s120min=h16h=min速度單位：m/s,km/h1m/s=km/h1km/h=m/s10m/s=km/h4m/s=km/h20m/s=km/h12.5m/s=km/h30m/s=km/h18km/h=m/s36km/h=m/s7.2km/h=m/s108km/h=m/s54km/h=m/s密度單位：kg/m3g/cm31g/cm3=kg/m31kg/m3=g/cm37.9g/cm3=kg/m32.7g/cm3=kg/m30.9g/cm3=kg/m30.8g/cm3=kg/m31.0×103kg/m3=g/cm38.9×103kg/m3=g/cm319.3×103kg/m3=g/cm30.8×103kg/m3=g/cm3科學計數(shù)法：10a×10b=10a+b10a/10b=10a-b10=101100=1021000=103110=0.1=10-11100=0.01=10-211000800=160=2000=0.0018=0.025=103104109=4×102105=5×5010-4=750×10-4=18×103=10-210答案：長度單位：km,m,dm,cm,mm,μm,nm1km=103m=106mm=109μm=1012nm1m=103mm=106μm=109nm1nm=10-3μm=10-6mm=10-9m1m=10dm=102cm=103mm1mm==10-1cm10-2dm=10-3m1m=10-3km1cm=10-2m1dm=10-1m1μm=10-6m1cm=10-5km170cm=1.7m8dm=0.8m0.005m=5×10-3m36m=3.6×10-2km760mm=76cm48km=4.8×104m54km=5.4×104m面積單位：m2，dm2，cm2，mm21m2=102dm21m2=106mm21m2=104cm21cm2=10-4m21dm2=10-2m21mm2=10-6m2100cm2=10-2m28000cm2=0.8m2500cm2=5×10-2m260cm2=6×10-3m29cm2=9×10-4m27.5cm2=7.5×10-4m238mm2=3.8×10-5m296dm2=0.96m2625cm2=6.25×10-2m245cm2=4.5×10-3m2體積單位：m3，dm3，cm3，L,ml1L=103ml1ml=10-3L1L=1dm31ml=1cm31m3=103dm31m3=106cm31dm3=103cm31cm3=10-3dm31cm3=10-6m360cm3=6×10-5m3400cm3=4×10-4m318cm3=1.8×10-5m3質(zhì)量單位：t，kg，g，mg1t=103kg1kg=103g1g=103mg1g=10-3kg1kg=10-3t50t=5×104kg650kg=0.65t13g=0.013kg480g=0.48kg8t=8×103kg5400kg=5.4t1500g=1.5kg時間單位：h，min，s1h=60min1min=60s1h=3600s0.5h=30min45min=0.75h30min=0.5h23h=40min13h=20min6min=360s10min=600s120min=2h16h=10min速度單位：m/s,km/h1m/s=3.6km/h1km/h=518m/s10m/s=36k4m/s=14.4km/h20m/s=72km/h12.5m/s=45km/h30m/s=108km/h18km/h=5m/s36km/h=10m/s7.2km/h=2m/s108km/h=30m/s54km/h=15m/s密度單位：kg/m3g/cm31g/cm3=103kg/m31kg/m3=10-3g/cm37.9g/cm3=7.9×103kg/m32.7g/cm3=2.7×103kg/m30.9g/cm3=0.9×103kg/m30.8g/cm3=0.8×103kg/m31.0×103kg/m3=1.0g/cm38.9×103kg/m3=8.9g/cm319.3×103kg/m3=19.3g/cm30.8×103kg/m3=0.8g/cm3科學計數(shù)法：10a×10b=10a+b10a/10b=10a-b10=101100=1021000=103110=0.1=10-11100=0.01=10-211000800