Consider the following statements:

1. If a quantity B is raised to power n ( Bn ), its relative error is given by \(n(\frac{\Delta B}{B})\)
2. When two quantities are multiplied or divided the relative error in the result is the product of relative errors in the multipliers.
3. Percentage error is calculated using instrumental error.
4. In a certain experiment, the mean absolute error ( Δ bmean ) for the 4 measurements b1, b2, b3, and b4 will be \(\frac {(| \Delta b_{1}| +| \Delta b_{2}|+| \Delta b_{3}|+| \Delta b_{4}|)} {4}\)

Which of the following statements are correct.