The conclusions of (b) and (c) remain true. Indeed, the unit circle is a path-connected space, and the upper semicircle supplies a path from to ; restricting the proposed closed cover or two-valued continuous function to that path reduces either claim to the corresponding result on .
The fixed-point conclusion (d) fails. For example, any nontrivial spatial rotation of the unit circle has no fixed point when ; the antipodal map is the simplest example.
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