Write any three points on maintenance of machines.

Explanation

**Step-by-Step Text Solution:**

1. **Regular Lubrication**: One of the key points in the maintenance of machines is to add and test lubricants frequently. Lubricants help reduce friction between moving parts, which minimizes wear and tear and prolongs the life of the machine.

2. **Protection from Environmental Factors**: It is important to keep the machine covered to protect it from dust and humidity. Dust can create additional friction between parts, while humidity can lead to rusting and corrosion. By protecting the machine from these elements, we can maintain its efficiency and longevity.

3. **Repair and Prevention of Rust**: Any cracks or damages on the machine should be painted or repaired promptly. This helps prevent rusting and further deterioration of the machine's components. Regular inspections can help identify these issues early.

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