Hess's Law?

Question

Given the following data:
CaO(s) + CO2(g) → CaCO3(s) ΔH = -178.3 kJ
2Ca(s) + O2(g) + 2CO2(g) → 2CaCO3(s) ΔH = -1626.9 kJ

Find the ΔH of the following reaction:
2Ca(s) + O2(g) → 2CaO(s)

Given the following data:
S(s) + O2(g) → SO2(g) ΔH = -296.8 kJ
CS2(l) → C(s) + 2S(s) ΔH = -89.4 kJ
CO2(g) → C(s) + O2(g) ΔH = +393.5 kJ

Find the ΔH of the following reaction:
CO2(g) + 2SO2(g) → CS2(l) + 3O2(g)

Thank you before hand

Answer 1

CaO(s) + CO2(g) → CaCO3(s) ΔH = -178.3 kJ.....(1)
2Ca(s) + O2(g) + 2CO2(g) → 2CaCO3(s)ΔH = -1626.9 kJ..(2)
(2) - 2x(1):
2Ca(s) + O2(g) → 2CaO(s) ΔH = -1270.3 kJ

S(s) + O2(g) → SO2(g) ΔH = -296.8 kJ....(3)
CS2(l) → C(s) + 2S(s) ΔH = -89.4 kJ........(4)
CO2(g) → C(s) + O2(g) ΔH = +393.5 kJ..(5)
(5) - 2x(3) - (4):
CO2(g) + 2SO2(g) → CS2(l) + 3O2(g) ΔH = 1076.5 kJ