香港经济的主导产业是（    ）

    Today is Saturday. Jim doesn't have to go to school. And Mom will take him to the supermarket (超市). So he is very happy.

    “Mom, can you buy me a basketball, please?” Jim asks.

    “OK,” Mom says.

    Jim takes his hat and goes out with his mom. They get to the supermarket soon. It is very big, and many things are on sale. The basketball is very cheap (便宜的). It's only 35 yuan. So Jim buys two. One of them is for his good friend Mike, because Jim wants to go to Mike's house (房子) and play with him after lunch. Well, Mike must be very happy to get the basketball. And the two friends will play basketball and watch TV in the afternoon.

阅读表达。阅读上文，根据其内容完成下列各小题。

（ 1 ）∠B+∠BCD=180°；（2）∠1=∠2；（3）∠3=∠4；（4）∠B=∠5．

能判定AB∥CD的条件个数有（   ）