1. The biggest asset of Hindustani classical is the framework of Raag (Raag Vyawastha). Why do we need this framework and how does it help?2. How is one raaga’s mood defined? Who defines them? For eg: What is Marwah’s feeling3. In one of the interviews, Vasant Rao Deshpande mentioned that once Asa-ali khan Saheb sang Marwah and he realised span of Marwah is so huge. What does this span / canvas mean?