Question

1. Let A and B be sets. The set B is of at least the same...

1.

Let A and B be sets. The set B is of at least the same size as the set A if and only if (mark all correct answers)

there is a bijection from A to B
there is a one-to-one function from A to B
there is a one-to-one function from B to A
there is an onto function from B to A
A is a proper subset of B

2.

Which of these sets are countable? (mark all correct answers)

the set of all 3-tuples (a,b,c), where a, b, and c are integers
the set of all real numbers
the set of all infinite sequences over natural numbers
the set of irrational numbers
the set of all functions from R to {0,1}
the set of all binary strings of length 113
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