下列命题：

（1）圆既是轴对称图形又是中心对称图形；

（2）平分弦的直径垂直于弦；

（3）相等的圆心角所对的弧相等．

其中真命题有（　　）个．

A: Hello Sandy This is Mary speaking, ____？

B. I'm Xi'an

A. Are you taking a holiday there?

B. Yes.  ____？

A: I'm writing a report.

B: ____?

A: It's about the population.

B: Well, I think you can write about the population of Xi' an.

A: Good idea. ____?

B: More than 8 million.

A: Is the population of Xi'an larger than that of Dalian?

B: ____Let me ask my father. Maybe he knows it.

A: All right.

古代学者甲认为，要把握“理”，需要“格物致知”；学者乙则认为“理”就像太阳、月亮一样明显，只要内心反省就能体会。学者乙是(  )