Dvat annexure 2c and 2d-urgent

Anybody has filled dvat annexure 2C and 2D......please tell me the below mentioned details:-

Amount of the relevant tax invoice affected by credit debit note:-.......(here bill amount to be mentioned or only sale amount to be mentioned)

Amount of the debit/credit note..............................................(bill amount or sale amount???)

Amount of variation to the tax amount shown in the tax invoice...............what does it mean?