How many moles are in 7.12 x 10^21 atoms of iron?

To Find :

How many moles are in atoms of iron.

Given :

We know, 1 mole of any element or compound contains exactly ( Avogadro's Number ) atoms/compound .

Now,

So, number of moles in given number of atoms are :

Hence, this is the required solution.

answer; /// i do believe that the correct answer is (a) boiling