You're talking about something which can't be done. Even if you did manage to manipulate the wiring so that you could, you'd only be blending the two air sources - something which a car's HVAC system does, anyhow.
More than likely yes.
No.
No.
While running your air conditioner, the vents should be closed so that warm air from out side do not enter into the room,which may cause damage to the machine in the long run and it will fetch more time to cool the room.
If it smells sweet ,it is coolant, and the heater core has failed. If it smells electrical you have a wiring problem and need to remove whatever is necessary to find cause.
A bad compressor belt can cause a whistling noise while running the air conditioner. A bad engine can also cause this noise.
No, it wont. And furthermore, it is not a good conditioner. It is cheap and can cause damage.
You may smell coolant when the ac is running but a leak in the heater core won't cause the ac not to work.
The chemicals in shampoo and conditioner can cause damage to your hair if used too often.
Yes But: Breathing the anti-freeze fumes is not good for humans. Also running out of coolant and engine overheating will cause damage. If it's an emergency, bypass the heater core with a hose and clamps to route coolant back to engine.
Heater core is leaking. Air Conditioner drain hose is plugged.
No, but it can cause severe engine damage if you keep running the engine.