Only if it's leaking.
Example sentence - The coolant in my car was leaking out.
Refrigerant - not coolant - and no, they are not compatible.
No. Use Coolant from honda dealership
you use a car
The company that makes the all model coolant claims you can.
No
In short no. Your cars cooling system is a sealed unit therefore it should not use any coolant whatsoever no matter the ambient temperature.
because it's used in your engine as coolant
Because it's attached to the engine and uses power when you turn it on. Even if it wasn't attached to the engine, anything in or on a car that takes power in some form will use fuel because ultimately it's the engine that supplies that power.
50 percent coolant, 50 percent water
No... But it increases fuel consumption
use the factory coolant that came with the car in otherwords don't change the color of it if your unsure what was original if unsure of the original go with the green.