Explain how the power of the Union to confer powers on States works, as per clause (2) and clause (3).
Clause (2) and clause (3) of the context provided outline a mechanism for the Union government to delegate certain powers, duties or functions related to the executive power of the Union to the state governments. This may happen when the central government requires assistance from the states in specific areas, such as constructing or maintaining communication infrastructure or protecting railways, as described in the context.

The process involves the President's agreement with the state government and can be done either conditionally or unconditionally. In some cases, a law made by Parliament that applies to a certain state may also confer powers and impose duties upon the state, its officers, or authorities, even if it relates to an area where the state legislature has no power to make laws.

When such delegation occurs and the state incurs extra costs in carrying out these additional responsibilities, the central government is required to compensate the state for those extra costs as per the provisions outlined in the context.