On the fourth day of the fourth lunar month, the moon is located at 45 degrees west of the sun, and it can generally be considered that its trajectory is three hours behind the sun. That is to say, around 9 am, it rises quietly in the morning light. It was not until after sunset that the glow faded that the moon could be found in the southwest sky (do you think this was the position of the sun three hours ago? )
Of course, if you want a more accurate answer, you need to provide the latitude, longitude and date of the observation point, so that you can get results accurate to minutes or even seconds and milliseconds. But generally speaking, if you know more and think more about the law, the initial answer is enough.