$${W = W_g + W_T = 5,88 \times 10^4\, \mathrm{J} – 4,70 \times 10^4\, \mathrm{J} \\ = 1,18 \times 10^4\, \mathrm{J} \approx \underline{\underline{12\, \mathrm{kJ}}}}$$