Sixty-three joules of heat are added to a closed system. The initial internal energy of the system is 58 J, and the final internal energy is 93 J. How much work is being done by the system?

Sixty-three joules of heat are added to a closed system. The initial internal energy of the system is 58 J, and the final internal energy is 93 J. How much work is being done by the system?