In an adult human being, the total volume of the blood is about _________litres.

Explanation

To answer the question regarding the total volume of blood in an adult human being, we can follow these steps:

1. **Understand the Question**: The question asks for the total volume of blood in an adult human being, which is a specific measurement in liters.

2. **Recall Basic Knowledge**: It is important to remember that blood is a vital fluid in the human body, responsible for transporting oxygen, nutrients, and waste products.

3. **Identify the Average Volume**: Based on biological knowledge, the average volume of blood in an adult human is typically between 5 to 6 liters.

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