What are the legislative relations between the Union and the States according to Part XI of the Constitution?
The legislative relations between the Union and the States according to Part XI of the Constitution are as follows:

1. Subject to the provisions of the Constitution, Parliament may make laws for the whole or any part of the territory of India, and the Legislature of a State may make laws for the whole or any part of the State.
2. No law made by Parliament shall be deemed to be invalid on the ground that it would have extra-territorial operation.
3. The legislative powers between the Union and the States are distributed in various subjects specified in the Seventh Schedule, which is divided into three lists: Union List, State List, and Concurrent List. Each list contains specific matters for which the respective legislatures can make laws.
4. In case of conflict or inconsistency between the laws made by Parliament and a State Legislature on any matter enumerated in the Concurrent List, the law made by Parliament shall prevail over the law made by the State Legislature.
5. The President may, with the consent of the State Legislature, make an agreement with that State for the exercise of any executive power or the rendering of any advisory opinion to the President by the State Governor.
6. Any amendment of a law related to any matter specified in sub-clause (a) or (b) of clause (2) shall require the assent of not less than two-thirds of the members present and voting in each House of Parliament.