The 50/50 mix is correct however there are many variables , if you have an overflow or expansion tank it is to the max line cold, assuming you are filling your system from empty there will be in your owners manual how's many quarts your system holds .

the normal is a 50/50 mix of coolant (antifreeze) and water. If you are driving something special, check with a dealer or a shop.

One half the total cooling system capacity. Read what the capacity is in the specifications page of the glove compartment manual.

we need to know the type of cart. most of the time, it is a 50/50 mix. there are some that go to 75/25.

There should be a measuring guideline for cars if you do a quick search on the Internet. Just type in model, year and you will find it. Also they still sell car manuals.