Which equation correctly represents the distance between −15.1 and −3.9 on a number line?

|−15.2+(−3.9)|=19
−15.1−3.9=−19
−3.9−15.1=−11.2
|−3.9−(−15.1)|=11.2 help meeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee∵∵∵∵