下列金属制品的用途中，利用导热性的是（　　）

某同学从平面镜前1.5m处走近平面镜，则该同学在平面镜中的像（　　）

Helen is 15 years old, and Joan is 15, too. So Helen is ____ Joan.

如果有理数a,b满足 $|ab-2|+{(1-b)}^2=0$ ，试求 $\frac{1}{ab}+\frac{1}{(a+1)(b+1)}+\frac{1}{(a+2)(b+2)}+\cdot \cdot \cdot +\frac{1}{(a+2007)(b+2007)}$ 的值。

The confidence of the Chinese film makers ______ by Avatar, the release of______ has not only set a good example for the Chinese film industry but also embarrassed our directors, who lack professional ethics.