Detailed explanation of the answer to the sixth question of the Ministry of Education
1. Select Julian
Hook certainly doesn't know anything, because she is the first.
Sister must know nothing, because her eyes are blindfolded.
Julian didn't know it at first, because he could only see the white flowers in front of Hook.
5. However, when Luca didn't know, the problem came:
If there are two white flowers or two purple flowers in front, Luca will know if she is a purple flower or a white flower.
But Luca doesn't know, which means there is only a white flower or a purple flower in front.
If Julian moves his little head and eliminates the white flowers on Hooke's head, then he can know that his head is purple.