According to IUCN 2004 what is the total number of known plants and animals specis ?

Explanation

**Step-by-Step Solution:**

1. **Identify the Organization**: The question refers to the International Union for Conservation of Nature (IUCN), which is responsible for assessing the conservation status of species and providing data on biodiversity.

2. **Reference the Year**: The question specifically asks for data from the year 2004, which is important for contextual accuracy.

3. **Recall the Data**: According to the IUCN's findings in 2004, the total number of known plant and animal species was reported.

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