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[6 points] Let R2 be endowed with the Euclidean topology, Which of the following are compact subsets of R2? Select one or more: 0 a. The set {(1,12) : n e N} u {(0,0)}. 0 b. The set {7, 4] x [3, 12]. O c. The closed annulus {(x, y) e R2 | 1 5 x2 + y2 5 9}. D d. The set (0, 1) x [2, 3]. D e. The line [(x,y) e R2 Ix + 2y = 7}