Need help with the last one I keep getting it wrong. Please Help!!!?

I tried but I can't help me please?
Burning 0.510 g of ethanol resulted in a 10.00 ∘C rise in the temperature of the 200.0 mL of water in the calorimeter. Assume that the calorimeter is not perfect.
1-How much energy was released by burning 0.510 g of ethanol? =15.17
2-How much energy is required to raise the temperature of 200.0 mL of water by 10.00 ∘C?=8.37
3, A: How much energy was lost to the surroundings in this calorimetric experiment? Express this value as a total number of kilojoules as well as a percentage of the total heat released by burning ethanol.
kilojoules of energy loss =6.8
percentage of energy loss =45
4-What is the heat capacity of this calorimetric apparatus (????cal)?=  676 but it’s wrong