分解因式：

（1）2a（a-b）-b（b-a）；                              

（2）4x³-9x．

小题1:Why does the writer introduce so many animals from different places to us?

A．To frighten us in the zoo.

B．To make us lovely in the zoo.

C．To attract us to the zoo.

D．To show that animals can do everything.小题2:How much does Mr. Smith have to pay if he visits the zoo with his two-year-old son?

A．￥3.

B．￥4.

C．￥5.

D．￥6.小题3:At which of the following time can we visit the zoo?

A．8:30 a.m. Wednesday.

B．9:30 a.m. Friday.

C．3:00 p.m. Sunday.

D．5:00 p.m. Tuesday.