Let B be the closed ball in $\Bbb R^2$ with centre at the origin and radius unity. Pick out the true statements.
(a) There exists a continuous function $f : B \to\Bbb R$ which is one-one.
(b) There exists a continuous function $f : B \to\Bbb R$ which is onto.
(c) There exists a continuous function $f : B \to\Bbb R$ which is one-one and onto.
continuous image of a connected (compact) space is connected (compact). but how can i use this result in this problem