Identify the relation that is not a function. weight of an apple to the apple's cost time of day to the temperature at that time weight of a person to a person's height phone number to a person's name

Let x = weight and y = height. It is possible to have a certain weight correspond to multiple heights. This means the input x has multiple output y values. Therefore, we cannot have a function here. A function is only possible if for any x input, there is exactly one y output. The x value must be in the domain.

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