The combustion of a sample butane, c4h10 (lighter fluid) produced 2.46 grams of water. how much oxygen was used up in grams

The balanced combustion reaction for butane is;

2C4H10 + 13O2 → 8CO2 + 10H2O

Molar mass of water = 18.02 g/mol

Molar mass of oxygen = 32 g/mol

2.46g H2O(1 mol H2O/18.02g)(13 mol O2/10 mol H2O)(32g O2/1 mol O2) = 5.68g O2

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be

i believe the answer is 5,000