please guys help with number one

Dear Student,
1) 1 mole of Calcium Carbonate(CaCO_3^​​​​​​​​​) contains
6.02 ×10²³ molecules. 
Thus, mass of 1 mole of Calcium Carbonate will be
​​​​40 + 12 + 16×3 = 40 +12 + 48 = 100 g. 
Regards.