Abook rests on a table. the earth pulls down on the book through the weight force. which force is the reaction force to the weight force?

1. the force of the earth on the book
2. the force on the table on the book
3. the force of the earth on the table
4. the force of the book on the earth
5. the inertia of the book

Air is contained in a variable-load piston-cylinder device equipped with a paddle wheel. initially, air is at 400 kpa and 17°c. the paddle wheel is now turned by an external electric motor until 75 kj/kg of work has been transferred to air. during this process, heat is transferred to maintain a constant air temperature while allowing the gas volume to triple. calculate the required amount of heat transfer in kj/kg.