1. The operation © is defined on the set S = {a, b,c}, as shown in the following table. For example, a©b=b and b © a=b ,c ©a=c. a a. Is S closed with respect to ©? b. Is © commutative on set S? c. Is there an identity for © on S? If yes, what is it? d. Is © associative on S? 2. Give a set that is not closed under addition. 3. Is the set of whole numbers commutative under subtraction? If not, give a counter example.

i think it is everything has to equal 180 so, if i correct 4=c. 6=d. 8=a. 7=b. and the last question would be c. because they are parallel lines and they are congruent.

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the reason everything has to equal to 180 is because that is how it works. i'm guessing that is its rule. 4 and 8 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 6 and 7 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 60+60 is 180. so, now you have your answer

the correct answer is 5 6 and 7

well the answer to that is xoxoxo

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many reason,

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