图中平行四边形的面积是8.4平方分米，阴影部分的面积是____平方分米．

阅读下面语篇并根据语篇内容回答问题
    A train stopped at a small station. A man on the train looked out of the window and saw a woman. The woman was selling cakes, and the people from the strain bought them. The man wanted to buy a cake, but the woman was far away from him. It was raining, and he didn't want to go out. Suddenly he saw a boy. The boy was walking on the flatform（月台）not far from him. “Come here.” He said to the boy, “Do you know how much each of the cakes is?” “Five cents（分）.” The boy answered. The man gave the boy ten cents and asked him to buy two cakes. “One is for me and the other is for you” he told the boy. Some minutes later, the boy came back. He was eating a cake. He gave the man five cents and said, “There was only one    cake left（剩下的）.”

根据表中数据回答：假如让你架设一条输电线路，在铜线和铝线之间，你应选用____；假如要选用一根金属丝来做滑动变阻器的电阻丝，在镍铬合金和锰铜丝之间，你应选用____．

任务型阅读

　　At present, there is much homework for American students. But home is not a good place for students to do their homework. So there come Homework Clubs. And they are more and more popular in America.

What is the Homework Club?

The Homework Club is a good place for students to do their homework. It is very quiet. A teacher will help students prepare for the tests there. The teacher is not to teach students but to give them help when they need.

Where is the Homework Club?

The Homework Club is usually in a library or in a classroom. It is a popular activity after school every day. If there is no school that day, Homework Clubs will NOT meet.

What will students do in the Homework Club?

In the Homework Club, the students will do their homework for the first hour and then they will draw pictures or play football.

根据短文内容填空。