That is called condensation
It mean it consisted of 1 g of lead and 0.077 g of O2.
divide these numbers by molar mas.
1/82=0.012 Pb /0.004 = 3
0.077/16= 0.004 O /0.004 =1
Pb3O
The answer is A. Na
because it's<span /> 5,1391
Coal can replace petroleum base fuel when you are just heating something that dont need big amount of heat. examples of it is when producing steam, coal is just used to heat water and produce steam because coal is much cheaper and the coal can already do the job in heating the water