No. Not if it is in proper working order.
gravity assuming the car was off, and not in park
Obviously, if not put into P (PARK), then yes.
No, No car equipped with an automatic transmission should, unless the linkage is out of adjustment and it is not going into park.
a few inches is normal at first when shifting but if it continues to roll the parking gears are probally broken
the car will probably roll backwards or forwards if it is on a hill. If the car is on a flat area of the ground, nothing.
I have read that the piece in the transmission that holds a car in park can break. I would just use the parking brake each time.
You park in the basement car park.
Yes, most definitely it will roll down the hill. When parking on a hill always set the parking brake. The park gear in an A/T can break, so do not take a chance. In drive the car will roll if the brake is not set.
yes but you will waste a lot of gas and you probably want to put it in park or it will roll away and you will die
You want to park the car with the front wheels turned toward the curb so if the emergency brake were to fail the car would simply roll into the curb and stop. Put the car in first gear if it is a manual tranny and set emergency brake.
Always turn your wheel to the curb, facing up or down hill; this allows for the car to roll out of the street in a worst-case scenario.