Gst question

A-IF a MFG CO.SELL GOODS WITHIN STATE WHAT TAX TO BE CHARGED B--IF A CO.SELL GOODS O/S WHAT TAX TO BE CHARGED WITH INVOICE FORMET C--ITC CREDIT RULES WHEN PURCHASE WITHIN STATE D---ITC CREDIT RULES WHEN PURCHASE O/S E--RETURN NO FORM FOR A MFG COMPANY