Union
$$A \cup B =$$
{ class, climax, exposition, fall, family, genus, kingdom, order, phylum, resolution, rise, species }
Symmetric Difference
$$A \ominus B =$$
{ class, climax, exposition, fall, family, genus, kingdom, order, phylum, resolution, rise, species }
Cartesian Product
$$A \times B =$$
{ (class, climax),
(class, exposition),
(class, fall),
(class, resolution),
(class, rise),
(family, climax),
(family, exposition),
(family, fall),
(family, resolution),
(family, rise),
(genus, climax),
(genus, exposition),
(genus, fall),
(genus, resolution),
(genus, rise),
(kingdom, climax),
(kingdom, exposition),
(kingdom, fall),
(kingdom, resolution),
(kingdom, rise),
(order, climax),
(order, exposition),
(order, fall),
(order, resolution),
(order, rise),
(phylum, climax),
(phylum, exposition),
(phylum, fall),
(phylum, resolution),
(phylum, rise),
(species, climax),
(species, exposition),
(species, fall),
(species, resolution),
(species, rise) }
Taxonomy (biology)