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
1. I think it's the trails left by an electron as it moves around the nucleus.
2. The atomic number is the number of protons so it is 8.
3. It's mass is lowered but it is still the same element.
The hydropower plant and wind turbines both uses kinetic energy to produce mechanical power and convert the mechanical energy using a generator to an electrical energy. They both have the process to produce energy but they differ in the source the hydropower plant uses water to whit the wind turbines power plant uses wind. Therefore the answer is letter B.
Evolution of sexual production
