A closed system like that shown in Fig. P4-29E is operated in an adiabatic manner. First,...

A closed system like that shown in Fig. P4-29E is operated in an adiabatic manner. First, 15,000 lbf ft of work are done by this system. Then, work is applied to the stirring device to raise the internal energy of the fluid by 10.28 Btu. Calculate the net  increase in the internal energy of this system.