如果方程组$\left\{\begin{array}{c}2x+3y=7\\ 5x-y=9\end{array}\right.$的解是方程3x+my=8的一个解，则m=（　　）

动物的生活环境不同，其运动方式也不尽相同．如蚯蚓的运动方式是（　　）

    Jack is not old, but he doesn't have much hair. His wife Alice has thick(厚的)and black hair.

    They have a daughter(女儿). Her name is Kitty. And Kitty is five years old. 0ne day, Jack is reading a book in his room. Kitty looks at her father for a long time and says to her mother,“Why does father have so little hair?”“He has little hair because(因为)he thinks a lot. He is a very clever(聪明的)man. ”Alice says with a smile(微笑).