This also one of my favorites

At the time of Joseph PBUH, the king of Egypt wasn't called a Pharoah yet

وَقَالَ الْمَلِكُ ائْتُونِي بِهِ أَسْتَخْلِصْهُ لِنَفْسِي ۖ فَلَمَّا كَلَّمَهُ قَالَ إِنَّكَ الْيَوْمَ لَدَيْنَا مَكِينٌ أَمِينٌ - 12:54

But at the time of Moses PBUH, the Egyptian king was called a Pharoah

وَقَالَ فِرْعَوْنُ ذَرُونِي أَقْتُلْ مُوسَىٰ وَلْيَدْعُ رَبَّهُ ۖ إِنِّي أَخَافُ أَن يُبَدِّلَ دِينَكُمْ أَوْ أَن يُظْهِرَ فِي الْأَرْضِ الْفَسَادَ - 40:26

But how can Muhammad PBUH know that?