Answer: 
Explanation:
Given
83% heat is transferred and out of this, only 40% is converted to the mechanical energy of spinning turbine.
The overall efficiency is the product of all the efficiency i.e.

Answer:
Technician B is correct
Explanation:
Unless the car owner just put oil in the car, the sudden distrust of the pressure sending unit is alarming.
Even if the car owner just replaced oil, so many other things can cause a running out of oil.
So, the better option is to check the oil pressure with a gauge outside of the car system before deciding to replace the pressure sending unit.