What are the differences between General Obligations and Disciplines and Specific Commitments under the GATS? Why does the GATS make such distinction and does the distinction affect the level of liberalisation under the GATS? Please cite appropriate Articles (for example Art. II (MFN Treatment) and Art. XVII (National Treatment)) and case law to support your answer. You may also compare such distinction with the GATT 1994. (Max. 2,500 words)