Answer:
1 mole of c12=6.022×10^23 
so 
1.24 mole of c12=1.24×10^23
Step-by-step explanation:
according to the mole concept 
no of mole is very important 
if u have that given its very easy to do the solving 
if not given go for the no of mole in mole concept for first 
and always remember the constant (6.022×10^23) and formulae