#### Answer

2 dm

#### Work Step by Step

First we can convert 0.0002 km to units of meters. We know that 1 km = 1000 m, so we can move the decimal point three places to the right.
0.0002 km = 0.2 m
Now we need to move the decimal point one place to the right. Therefore, we need to use a unit that is equal to 0.1 m and this unit is $dm$ (decimeter). We know that 1 m = 10 dm. We can convert 0.2 m to units of dm.
$0.2~m = 2~dm$
$0.0002~km = 0.2~m = 2~dm$