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You should be able to decide whether each of the following subsets of R\" is closed, open, both, or neither: (I) The subset IR\" itself. (II) The subset [ll C R\". (III) In R2, the set consisting of only the origin. (IV) In R1, the open interval from 1 to 1. (V) In R2, the set {($1,$2)|$1 = 0 and 1