What is the universal set for the following given sets: X={,,}, Y={,.}, Z={,}?

A. {a,b,c,d,e,f}
B. {a,b,c,e,f,g}
C. {a,b,c,d,e,g}
D. {a,c,d,e,g}
Other:

2.If A = {2,3,4,5},and B = {4,5,6,7}, what is A ∪ B?

A. {2,3,4,5,6,7}
B.{1,2,3,4,5,6,7}
C. {1,2,3,4,5,6} D.{2,3,4,5}
Other:

3. What is the term used to indicate the set of all elements?
A. subset
B. null set
C. universal set
D. empty set Other:

4. What is the symbol used to denote the union of a set?
A. U
B. A’
C. ∅ D.∈
Other:
5. Which of the following refers to the distance of a number from zero?
A. absolute value
B. integer
C. opposite
D.line
Other:

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