为加强对地方的控制，汉武帝设立十三个州部，其中十一个州的名称沿用了《尚书》、《周礼》中的州名。据此可以反映出（      ）

①中央集权趋于强化

②儒学地位上升

③地方行政区划变为州郡县三级制

④秦代以来的监察体制得到进一步完善

根据对话内容，从下面方框中选择适当的单词或短语填空，使对话内容完整正确。

A: Hello, nice to see you again.
B: Me too.
A: How is your holiday?
B: Great! I had a ____  holiday. I traveled to Japan with my parents.
A: Really? What did you see there?
B: I saw a lot of ____  ,such as Mount Fuji and Sanrio Puroland. Mount Fuji is so wonderful    that all of us want to climb up to the top. And Sanrio Puroland is the Hello Kitty’s land. We also  visited the Hello Kitty’s house. How lovely it is!
A: You must have a great time.
B:____  . How about you? What were you doing  ____  ?
A: I didn’t ____  . But I had a good time staying at home .I read a lot of books.
B: Oh, that’s interesting . It’s time to have lunch. I have to go. Bye.
A: Bye.

已知⊙O的半径为15，弦AB的长为18，点P在弦AB上且OP=13，则AP的长为（　　）