Tolong ubahkan ke noun clause

4. it is surprising that I met my old friend in the supermarket
5. I want to know where Ratna buy the dictionary 
6. I'm not sure what time it is
7. please tell me how long you will go to Manado
8. the reason why the accident happened is still unknown 
9. all students want to know who the principal is 
10. the way how the athlete reach that achievement inspires me