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Question

Consider the set ∑* of all strings over the alphabet ∑ = {0, 1}. ∑* with the concatenation operator for strings

a.

does not form a group

b.

forms a non-commutative group

c.

does not have a right identity element

d.

forms a group if the empty string is removed from ∑*

Answer: (a).does not form a group

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Q. Consider the set ∑* of all strings over the alphabet ∑ = {0, 1}. ∑* with the concatenation operator for strings

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