4. (5 points) [B,D] The string reversal operation takes as input a strings and outputs the...

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4. (5 points) [B,D] The string reversal operation takes as input a strings and outputs the same string in reverse order. For example (abcde)" = edcba. The language reversal operation takes as input a language L and produces as output a new language LR consisting of all the string reversals of strings in L. For example {abc, aa} = {cba, aa}. (a) (1 point) [B] Express the closure property that RE is closed under language reversal in first-order logic. (b) (2 points) [B] Give the generic element proof outline that RE is closed under language reversal. (c) (2 points) [D] Give pseudocode for the main procedure of the program that is part of this proof. 4. (5 points) [B,D] The string reversal operation takes as input a strings and outputs the same string in reverse order. For example (abcde)" = edcba. The language reversal operation takes as input a language L and produces as output a new language LR consisting of all the string reversals of strings in L. For example {abc, aa} = {cba, aa}. (a) (1 point) [B] Express the closure property that RE is closed under language reversal in first-order logic. (b) (2 points) [B] Give the generic element proof outline that RE is closed under language reversal. (c) (2 points) [D] Give pseudocode for the main procedure of the program that is part of this proof.

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a The closure property that RE is closed under language reversal can be expressed in firstorder logic as follows LLR R s L Rs LR r LR Rr L In this logic statement L represents the original language LR ... View the full answer