vat on MRP

I have purchased some goods in BIg Bazar, Tarnaka Branch, Secunderabad, few days ago. Items include oil, soaps, fruits, rice etc amounting to Rs 3800/- they charged vat on some items. Soaps, Oil were charged with vat and total vat amount is @ Rs 300.

The Question is. Is Vat is inclusive MRP or exclusive MRP ?
Is it Payable on the margin of the retailer or on the product rate ?
is the retailer bound to pay vat for the goods he purchases for the sale purpose when the purchases from the C@F agent are not ?

-AarisMohammed