Why must a measurement include a number and a unit

 Hey ! A measurement must include both a number and a unit because a number is meaningless without a unit; a unit describes what the number is measuring.The number specifies the finite value and the unit specifies the increment and describes what is being measured (length, weight, force, etc)..

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i think is 3 and 6. this took me 10 min to think.hope to and hope that my answer is brainliest.(follow me )