Choose the best answer for each situation.The EPA scientist measures the pH level in one area of a river to be lower than normal and writes that a pollutant must have been discharged from a factory just upstream. This is an example of .

The scientist directly observes or measures that the river’s pH is lower than normal. Concluding that a factory discharged a pollutant is an inference because it is an explanation drawn from that measurement, rather than something directly observed.

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