Answer:
1) H - hydrogen - 1.100797
2) HE - helium - 4.00260
3) LI - lithum -6.941
Explanation:
On the periodic table the mass of carbon is reported as 12.01 amu. This is the average atomic mass of carbon. No single carbon atom has a mass of 12.01 amu, but in a handful of C atoms the average mass of the carbon atoms is 12.01 amu.