A.60kN,40kN,-25kN B.60kN,40kN,25kN C.-60kN,-40kN,25kN D.-60kN,-40kN,-25kN

A.60kN,40kN,-25kN B.60kN,40kN,25kN C.-60kN,-40kN,25kN D.-60kN,-40kN,-25kN

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