(N/A) $1$. Error in measurement: An error is the difference between the measured value and the true value of a physical quantity. It is an inherent uncertainty in any measurement due to limitations of instruments,environmental factors,or the observer's technique. Errors are classified into systematic and random errors and cannot be completely eliminated,only minimized.
$2$. Mistake in measurement: $A$ mistake (or blunder) is an error caused by human carelessness,such as misreading a scale,incorrect recording of data,or using the wrong formula. Unlike errors,mistakes are avoidable and can be eliminated by being careful and verifying the procedure.