g No frictional losses occur through the pipe and no heat is transferred to the surroundings. 1. Frictional losses occur increasing the entropy by 0.01 kJ/(kg K) by the end of the pipe. No heat is transferred through the pipe wall and no other work occurs. 2. The pipe is twice as long increasing the entropy by 0.02 kJ/(kg K) by the end of the pipe. No heat is transferred through the pipe wall and no other work occurs. 3. Somehow, the entropy drops by 0.005 kJ/(kg K) through the pipe by the end of it. No heat is transferred through the pipe wall and no other work occurs. (This is actually impossible in real life, but see what happens)