食物链的起始环节是消费者．

已知集合$M=\left\{y|y=2^x,x>0\right\},N=\left\{x|y=lgx\right\}$，则$M\cap N$为 (    )

如图，两个四边形关于直线l对称，∠C＝90°，试写出a，b的长度，并求出∠G的度数．

    Hi, my name is Li Tong. I'm from a big city. My parents are doctors in a hospital. I'm in Class 1. Mr Mu's class. He is a Chinese teacher. My favourite subject is history. I like reading history books in the library. On Saturday, I play basketball with my friend Su Qi. Fish is my favourite food.

Hello, I'm Su Qi. I'm from the farm near the city. My parents are farmers. I'm in Class 3. Miss Bi's class. She is a maths teacher. English is my favourite subject. I can see a lot of vegetables on the farm. So I like reading the books about vegetables. Noodles are my favourite food.