Check all true statements. the cardinality of a x b is the sum of the cardinalities of a and b. if a={1,2} and b={3} then a x b ={ (1,3), (2,3) }. if a={1,2} and b={3} then a x b ={ {1,3}, {2,3} }. the cartesian product is symmetric, i. e. a x b = b x a for all sets a, b. the cartesian product is associative, i. e. (a x b) x c = a x (b x c) = for all sets a, b,c. both sets are equal to a x b x c. the cartesian product has a cancellation property, i. e. if a x b = a x c for some sets a, b,c and a nonempty, then b = c. the cartesian product has a cancellation property, i. e. if a x b = a x c for some sets a, b,c, then b = c. the power set of the cartesian product of a and b is the cartesian product of the power sets of a and b. if a x b = c x d, and none of these sets are empty, then a=c and b=d.