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Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

Let the closed interval [a , b] be the domain of function f. the domain of f(x - 3) is given by (a) the open interval (a , b) (b) the closed interval [a , b] (c) the closed interval [a - 3 , b - 3] (d) the closed interval [a + 3 , b + 3]

Closing a credit card usually _your debt ratio.a. increasesb. decreasesc. improvesd. has no effect on