Here are the question words that correspond to the answers:

1. They are my teacher. - **Who**
2. It's a mouse. - **What**
3. Those are mangoes. - **What**
4. That is the President. - **Who**
5. They are Mike's friends! - **Who**
6. That is the Eiffel Tower. - **What**
7. They are my parents. - **Who**
8. It's an old book. - **What**
9. They're students at my school. - **Who**
10. They're pyramids. - **What**