A = (200 k g \cdot 5 m + 25 k g \cdot 2, 5 m) \cdot 9, 8 N / k g \approx 10, 4 k J

${A=({200}\,\mathrm{kg}\cdot {5}\,\mathrm{m}+{25}\,\mathrm{kg}\cdot {2,5}\,\mathrm{m})\cdot {9,8}\,\mathrm{N/kg} \approx {10,4}\,\mathrm{kJ}}$

Error