长度\x051 m =1×10³ mm =1× 10^ 6μm （微米）=1× 10^ 9nm（纳米）面积\x051m² =1× 10 ²dm² =1× 10 ^4cm² =1× 10^ 6mm²体积\x051 m ³ =1× 10 ³dm ³（升L）=1×...