Cst sales transction

Dear All,

pls explaint the following transaction accounting

1.i want to made a thrid party sale. A, B & C-All are the people

A-in maharashtra

B- in maharashtra- for 1st case.  & out of maharashtra for 2nd case.

C-out of maharashtra

Cases

1.) A purchase a goods  from B & sale it to C. in this case what is the excise effect & CST or Vat

2.)A Purchase a goods from B & sale it to C. in this case what is the excise effect & CST or Vat