Calculate the number of atoms in 46.0 grams of Calcium 9(Ca)
I don't know what calcium 9 is but I suspect a typo.
There are 6.02E23 atoms in 1 mol Ca and 1 mol Ca is 40.08 grams. You have 46.0 g; therefore, you have 46.0/40.08 mols. Can you take it from there?