Calculate %composition of element in the following compounds-Na2Co3.10H2O

Answer 1

Done just like % composition of anything; i.e., (mass of the desired constituent/mass whole thing)* 100 = ?
%Na = (2*atomic mass Na)/molar mass Na2CO3,10H2O
% C = atomic mass C/molar mass Na2CO3.10H2O
Etc
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