How to Density of Methanol Please Help!

Here is the question. I have tried very hard and can't seem to get it. The density of methanol (CH3OH) is 0.787 g/mL at 20 degrees C. The energy released in the burning of methanol is 726 kJ/mol. Calculate the heat in Joules released when 10.0 mL of methanol burns. Please help and explain this to me, it is very urgent.

(10.0 mL CH3OH) x (0.787 g/mL) / (32.042 g CH3OH/mol) x
(726 kJ/mol) = 178 kJ = 1.78 x 10^5 J

(4.56 x 10^20 molecules) / (6.022 x 10^23 molecules/mol) x
(194.1915 g C8H10N4O2/mol) = 0.147 g = 147 mg C8H10N4O2

Au2(SO3)3 = 634.1245 g/mol
(O3)3 = 143.99487 g/mol

(143.99487 g/mol) / (634.1245 g/mol) = 0.22708 = 22.708% O in Au2(SO3)3

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