Which of the following relations is a function?

{(-2, 3), (4, 1), (0, 0), (-2, 2)}
{(1, 1), (2, 2), (1, 2), (2, 1)}
{(2,3), (3, 2), (6, 3), (3, 6)}
{(6,5), (5, 6), (3, 1), (1,3)}

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Fred has a spinner that is split into four equal sections: red, blue, green, and yellow. fred spun the spinner 688 times. which of the following would be a good estimate of the number of times the spinner lands on the green section? a. 269 b. 603 c. 344 d. 189

The area of a rectangle is 10 cm^2. one side of the rectangle is x cm. express the perimeter of the rectangle in terms of x and show that this rectangle cannot have a perimeter of 12 cm. the perimeter of the rectangle in terms of x is __ cm