All possible values of x

Give all possible values of x that can result from executing

(define x 10)

(parallel-execute (lambda () (set! x (* x x)))
                  (lambda () (set! x (* x x x))))

Which of these possibilities remain if we instead use serialized procedures:

(define x 10)

(define s (make-serializer))

(parallel-execute (s (lambda () (set! x (* x x))))
                  (s (lambda () (set! x (* x x x)))))

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