Technician a says that if the cooling system has been exposed to the air for more than 24 hours, the drier should be replaced. technician b says that repairs should be made before refrigerant is evacuated from a system. who is  correct?  
            a.  both technicians a and b    b.  technician b    c.  technician a    d.  neither technician a nor b

Option A. Both Technicians A and B

Explanation:

Both technicians are correct. There are fundamentals that have to be understood regarding cooling systems.

The cooling system depends on a thermodynamic system that involves the expansion and compression of the cooling fluid. In addition, the coolant is the one that circulates in the pipes influencing convention currents between the pipes (coiled pipes) or otherwise. It is noteworthy that the dryer be kept out of the reach of moisture as this will corrode. Therefore, a drier that comes in contact with moisture needs to be replaced as this brings about corrosion.

In addition, it is also very important to remove the refrigerant from the system so that there will not be extreme fluctuations in temperature and pressure. In order to be on the safe side, the refrigerant needs to be replaced.  

thermal energy is the answer