Consider the ring (Z, 0, 0) where and are defined as follows a b = a+b-1 a ob = a+bab (a) Is the given ring commutative? Justify your answer. (b) Find the additive identity in the ring. (c) Does the ring have a unity? If yes, what is the unity? Justify our answers. (d) Is the ring a field? an integral domain? Justify your answers.