Answer:
yes, f is a function from A to B
Explanation:
If a set of ordered pairs is to be considered a function from A to B, then:
1) Each element from set A must be paired with exactly one element from set B, AND,
2) No two distinct elements from set A can be paired with the same element from set B.
In the given set of ordered pairs {(a, 4), (b, 5), (c, 6)}, each element from set A is paired with exactly one element from set B. This satisfies condition 1).
Also, there are no repeated elements from set A in the given pairs. This satisfies condition 2). a is paired only with 4, b is paired only with 5 and c is paired only with 6.
Therefore, because f satisfies both conditions, it is a function from A to B.