Mark the correct alternative in each of the following:

A binary operation * on Z defined by a * b = 3a + b for all a, b ∈ Z, is

Mark the correct alternative in each of the following:

An operation * is defined on the set Z of non-zero integers by for all a, b ∈ Z. Then the property satisfied is

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On Z an operation * is defined by a * b = a² + b² for all a, b ∈ Z. The operation * on Z is

Mark the correct alternative in each of the following:

Let * be a binary operation on Q⁺ defined by for all a, b ∈ Q⁺. The inverse of 0.1 is

Mark the correct alternative in each of the following:

Let * be a binary operation on N defined by a * b = a + b + 10 for all a, b ∈ N. The identity element for * in N is