The units are nm (nano-meter), km (kilo-meter), pm (pico-meter), dm (decimeter), mm (millimeter), m (meter), cm (centimeter), hm (hectometer) and gm (gigameter). Now we can express each of these units in terms of m.
1 nm = [tex]10^{-9}m[/tex], 1 Km = [tex]10^{3}m[/tex] 1 pm = [tex]10^{-12}m[/tex], 1 dm = 0.1 m, 1 mm = 0.001 m, 1 cm = 0.01 m, 1 hm = 100 m, 1 gm = [tex]10^{9} m[/tex]. Thus the decreasing unit will be
gm>km>hm>m>dm>cm>mm>nm>pm
