Mixture of iron fillings and sand can be separated by ________

Explanation

**Step-by-Step Solution:**

1. **Identify the Components of the Mixture**: The mixture consists of iron fillings and sand.

2. **Understand the Properties of the Components**: Iron fillings have magnetic properties, while sand does not. This means that iron can be attracted to a magnet, but sand cannot.

3. **Choose a Separation Method**: Since one component (iron) is magnetic and the other (sand) is not, the most effective method for separation is magnetic separation.

4. **Perform the Separation**: To separate the iron fillings from the sand, take the mixture and place it in a container. Then, bring a magnet close to the mixture.

5. **Observe the Results**: The iron fillings will be attracted to the magnet and will stick to it, while the sand will remain in the container.

6. **Complete the Separation**: After the iron fillings have been attracted to the magnet, you can remove the magnet from the mixture, leaving the sand behind.

7. **Conclusion**: Therefore, the mixture of iron fillings and sand can be separated by magnetic separation.

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