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Acredit card advertises an annual interest rate of 23%. what is the equivalent monthly interest rate?

1- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis.2- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in the first question?

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?