How close a measurement is to it's true or accepted value is

Review the branily terms and services guides well u know what i never did so go have a nice ice cream sunday

Ineed to find the answer of this question because i dont understand it

The table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 9 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of tthe table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 9 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.