>>14055085With formula, you mean if you drew benzene, the formula would be C6H6?
The kinks in the line represent one carbon. Carbon can make 4 bonds. All the carbons in benzene are connected to 2 carbons. The rest of the bonds are assumed to be Hydrogen, to save time drawing it out. So each carbon on benzene is connected 2 two carbons and one Hydrogen.
So you just count the number of atoms. Your OP is C8H10N4O2.