Union
$$A \cup B =$$
{ Inheritance, question, read, recite, review, selection, survey, time, variation }
Symmetric Difference
$$A \ominus B =$$
{ Inheritance, question, read, recite, review, selection, survey, time, variation }
Difference
$$A - B =$$
{ question, read, recite, review, survey }
Difference
$$B - A =$$
{ Inheritance, selection, time, variation }
Cartesian Product
$$A \times B =$$
{ (question, Inheritance),
(question, selection),
(question, time),
(question, variation),
(read, Inheritance),
(read, selection),
(read, time),
(read, variation),
(recite, Inheritance),
(recite, selection),
(recite, time),
(recite, variation),
(review, Inheritance),
(review, selection),
(review, time),
(review, variation),
(survey, Inheritance),
(survey, selection),
(survey, time),
(survey, variation) }
SQ3R