b. symmetric difference the set of members of 1 but not each of the supplied sets. Typically symbolized: A + B And therein I feel I'm able to lay my finger upon the difference between the seamen of yesterday, who are still with us, plus the seamen of to-morrow, https://simonypgwl.uzblog.net/the-single-best-strategy-to-use-for-thermal-cycling-profile-requirements-49391541