物质X是一种重要的阻燃剂，工业上用三氧化二锑Sb₂O₃生产X的化学方程式为：Sb₂O₃+2H₂O₂═X+2H₂O．根据质量守恒定律，推断X的化学式为（　　）

2+____=16    ____-9=9    56÷____=7     ____ ×8=32

阅读短文回答问题

A: Could you tell me the way to the Sunshine School please?

B: Em, let me think about it.

A: I hope you can remind of it.

B: Yes, go down this street, then turn left at the third crossing（路口）, the Bus-stop is on your right, and you can take No. 10 bus to Sunshine School.

A: Wait...wait for a moment...I cannot catch it...Is it the first crossing?

B: No, the third crossing...

A: No. 10 Bus?

B: That's right. Are you clear?

A: Yes, clear. Thanks a lot.

B: You are welcome.

秦代万里长城和隋朝大运河都是古代的伟大工程，对历史发展影响巨大。二者历史影响的相似之处是（    ）