[Assess students' ability to recall and state precise definitions of compactness (open-cover), sequential compactness, and related notions in metric spaces; state and explain the equivalence of compactness and sequential compactness in metric spaces; state the Heine–Borel theorem in R^n (compact iff closed and bounded) and recognize standard examples and counterexamples (e.g., [0,1], (0,1), bounded non-closed sets), including the role of Bolzano–Weierstrass.]