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**rtrumpow** Here is what I have: 1.) Determine whethr each of the following relations is a function with domain {1,2,3,4}. For any relation that is not a function, explain why it isn't.

a.) f={1,1), (2,1), (3,1), (4,1), (3,3)}. - The answer in back of the book states the following: "Not a function; f contains two different pairs of the form (3,-)." What does the dash mean?

b.) f={(1,2), (2,3), (4,2)} - ?

d.) f={(1,1), (1,2), (1,3), (1,4) - ?

e.) f={(1,4), (2,3), (3,2), (4,1)} - ?