Statement 1: This statement is correct.
Parliament can make laws on a matter in the state list if the Rajya Sabha passes a resolution that it is necessary in the national interest. This is provided under Article 249 of the Constitution.
Statement 2: This statement is correct.
The resolution must be supported by two-thirds of the members of the Rajya Sabha present and voting. This is a special majority and is correctly stated here.
Statement 3: This statement is incorrect.
The statement says the resolution remains in force only for 6 months. This is incorrect. The resolution remains in force for 1 year and can be extended by passing a new resolution.
Therefore, only statements 1 and 2 are correct.