Sure! Here are the answers based on the passage:

1. **Where does Gong culture exist?**
Gong culture exists in the Central Highlands of Vietnam.

2. **How often is the Gong Festival held?**
The Gong Festival is held annually in the Central Highlands.

3. **What do artists do in the Gong Festival?**
Artists give gong performances, highlighting the gong culture of their own province.

4. **How is the gong sound a way to communicate with the ancestors?**
The gong sound is a way to communicate with the gods during special occasions in people's lives.

If you have any more questions or need further assistance, feel free to ask!