Of the system descriptions given below, which ones specify the same system and which different systems?

Of the system descriptions given below, which ones specify the same system and which different systems?

(a) A rigid container of volume V, with walls impermeable to matter, is divided into two compartments by a membrane also impermeable to matter. One compartment contains 500 g of gasoline, the other 100 g of oxygen gas.

(b)  Same as in part (a), except that the membrane has been ruptured and the gasoline and oxygen are mixed but not chemically combined.

(c) Same as in part (a), except that the molecules of gasoline are highly excited.

(d) Same as in part (b), except that most of the molecules of gasoline and oxygen have combined and formed water and carbon dioxide.