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Comment : Sets quiz
Comment : This quiz is designed to test your knowledge of basic concepts in sets.
Comment : It turns out that A is in fact the half-open interval { y: 0 < y <= 1 } (why?). But you did not need to know that to work out this problem.

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Question 1: Let A and B be sets. What does it mean if we say that x is an element of (A union B)?

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	x is an element of A and is also an element of B.
	x is an element of A.
	x is an element of B.
	x is an element of A, or is an element of B, or both.
	A is equal to B, and x is an element of both.
	x is an element of A, or is an element of B, but not both.
	x is equal to some element a of A plus some other element b of B: x = a + b.