PROLOG PROGRAM:

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Given the following Prolog code:

a(1).

a(a).

b(2).

b(3).

c(X,X) :- a(X).

c(X,Y) :- a(X),b(Y).

c(X,X) :- b(X).

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List al of the possible solutions, produced in prolog order, to the query:

?-c( A, B).

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Turn on the trace facility in Prolog to document the results