Convert 12 kilometers to meters.

Step 1 ：We know that 1 kilometer is equal to 1000 meters, so we can set up the conversion as follows: \(12\, km \times \frac{1000\, m}{1\, km}\)

Step 2 ：When we multiply, the kilometers cancel out, leaving us with only meters: \(12\, km \times \frac{1000\, m}{1\, km} = 12000\, m\)