MCQ
The blood does not flow back into the ______ when mitral valve closes.
- Aright ventricle
- Bright auricle
- ✓left auricle
- Daorta
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| X | 1 | 2 | 3 | 4 |
| P(X) | `1/3` | `2/9` | `1/3` | `1/9` |
1hen, the mean of this distribution is ______