The man is holding the suitcase at the same height above the surface of earth. So the gravitation potential energy remains the same.
<span>work done is force * displacement = weight * 0 = 0</span>
Answer
Given,
Energy absorbed, 
Energy expels,
Temperature of cold reservoir, T = 27°C
a) Efficiency of engine



b) Work done by the engine



c) Power output
t = 0.296 s



Explanation:
Mass and energy are closely related. Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy. For example, after heating an object, its increase in energy could be measured as a small increase in mass, with a sensitive enough scale.