1. In the case of an irrevocable trust, it cannot be done without the consent of the settlor and the beneficiary. ... In the case where the private trust is created through will, then the trust may be revocable or may be modified at any time during the lifetime of the author of the trust.
2. As per section 77 of the Indian Trust Act,1882, a trust may be extinguished or terminated if “its purpose becomes unlawful”. However, when a public charitable trust is properly and completely constituted, it becomes irrevocable, even though it is voluntary. Accordingly, there is no provision under the various Public Trusts Acts to legally terminate or dissolve a valid public charitable trust. However, the assets and liabilities of the trust can be transferred to another charitable trust having similar objects thereby the former trust can be dissolved. But a revocable trust can be dissolved as per the terms and conditions of the trust deed.
3. See the above answer.