C 1 000 mm.
Step 1: Recall the conversion factor between metres and centimetres.
1metre=100 centimetres
Step 2: Recall the conversion factor between centimetres and millimetres.
1centimetre=10 millimetres
Step 3: Convert metres to millimetres using both conversion factors.
1metre=100cm×1cm10mm
1metre=1000 mm
The correct option is C.
C1000mm
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