# SETS problem

this is another problem which i dont know how to start..im not sure which proof i should use to solve this problem
the problem is:
If A,B,C,and D are sets, does it follow
(A Φ B) Φ (C Φ D) = (A Φ C) Φ (B Φ D)
the symbol that is separting the characters is called the oplus symbol, thats the closet symbol i could find
the oplus symbol is a circle with one line going across it and one line going down

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