Please can I have help on question e as I’m really stuck. I promise I’ll give out brainiest

The relative atomic mass of element A : 6.075 u

The elements in nature have several types of isotopes

Isotopes are atoms whose no-atom has the same number of protons while still having a different number of neutrons.

So Isotopes are elements that have the same Atomic Number (Proton)

Atomic mass is the average atomic mass of all its isotopes

Mass atom X = mass isotope 1 . % + mass isotope 2.% ...

Element A

mass number of isotope 1 = 6 , percent : 92.5%

mass number of isotope 2 = 7, percent : 7.5

Relative atomic mass of element A

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.

the awnser is group 12