Express 45 mm in cm, m and km.

Answer

To express 45 mm in cm, m, and km, we will follow these steps:

### Step 1: Convert millimeters to centimeters
1. **Understand the conversion factor**: 1 millimeter (mm) is equal to 0.1 centimeters (cm).
2. **Calculate**:
\[ 45 \text{ mm} = 45 \times 0.1 \text{ cm} = 4.5 \text{ cm} \]

### Step 2: Convert millimeters to meters
1. **Understand the conversion factor**: 1 millimeter (mm) is equal to 0.001 meters (m).
2. **Calculate**:
\[ 45 \text{ mm} = 45 \times 0.001 \text{ m} = 0.045 \text{ m} \]

### Step 3: Convert millimeters to kilometers
1. **Understand the conversion factor**: 1 millimeter (mm) is equal to 0.000001 kilometers (km).
2. **Calculate**:
\[ 45 \text{ mm} = 45 \times 0.000001 \text{ km} = 0.000045 \text{ km} \]

### Final Results:
- 45 mm = 4.5 cm
- 45 mm = 0.045 m
- 45 mm = 0.000045 km

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