小芳和小丽玩跳绳,用摸球游戏来决定谁先跳。布袋里有5个红球,1个黑球,摸到红球,小芳先跳;摸到黑球,小丽先跳。这样公平吗?为什么?
不公平,因为摸到红球的可能性大。
用所给动词的适当形式填空。
1. I'm learning _____ (speak) English.
2. He can't decide when _____ (start).
3. His greatest wish is _____ (see) an end towards.
4. I asked him _____ (show) me the new dictionary.
5. They felt the house _____ (shake) for a while.
6. He promised _____ (not tell) anyone about it
7. Wang Gang is always the first _____ (get) to the school in his class.
药典规定,在儿茶中测定儿茶素和表儿茶素含量的方法是
A.紫外-可见分光光度法B.薄层色谱扫描法C.高效液相色谱法D.气相色谱法E.滴定法