Union
$$A \cup B =$$
{ awareness, decision, gas, liquid, plasma, recognition, recollection, solid }
Symmetric Difference
$$A \ominus B =$$
{ awareness, decision, gas, liquid, plasma, recognition, recollection, solid }
Difference
$$A - B =$$
{ awareness, decision, recognition, recollection }
Difference
$$B - A =$$
{ gas, liquid, plasma, solid }
Cartesian Product
$$A \times B =$$
{ (awareness, gas),
(awareness, liquid),
(awareness, plasma),
(awareness, solid),
(decision, gas),
(decision, liquid),
(decision, plasma),
(decision, solid),
(recognition, gas),
(recognition, liquid),
(recognition, plasma),
(recognition, solid),
(recollection, gas),
(recollection, liquid),
(recollection, plasma),
(recollection, solid) }