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For each problem, say if the given statement is True or False. Give a short justification...

For each problem, say if the given statement is True or False. Give a short justification if needed.

Let f : R + → R + be a function from the positive real numbers to the positive real numbers, such that f(x) = x for all positive irrational x, and f(x) = 2x for all positive rational x.

a) f is surjective (i.e. f is onto).

b) f is injective (i.e. f is one-to-one).

c) f is a bijection.

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