…………ml of oxygen is transported per decilitre of blood.

Explanation

To solve the question of how much oxygen is transported per deciliter of blood, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Role of Hemoglobin**: Hemoglobin is a protein in red blood cells that binds to oxygen. It plays a crucial role in transporting oxygen from the lungs to the tissues.

2. **Identify the Amount of Oxygen Transported**: According to the information provided, approximately 19.5 ml of oxygen is transported in 100 ml of blood.

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