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Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

Which of the following best describes the graph below? + + 2 + 3 + 4 1 o a. it is not a function. o b. it is a one-to-one function. o c. it is a many-to-one function. o d. it is a function, but it is not one-to-one.

Varies inversely with x. if y=8.5 when x=-1 find x when y=-1