阅读下面材料：

根据两角和与差的正弦公式，有

sin（α+β）=sinαcosβ+cosαsinβ﹣﹣﹣﹣﹣﹣①

sin（α﹣β）=sinαcosβ﹣cosαsinβ﹣﹣﹣﹣﹣﹣②

由①+②得sin（α+β）+sin（α﹣β）=2sinαcosβ﹣﹣﹣﹣﹣﹣③

令α+β=A，α﹣β=B 有α= $\frac{A+B}{2}$ ，β= $\frac{A-B}{2}$

代入③得 sinA+sinB=2sin $\frac{A+B}{2}$ cos $\frac{A-B}{2}$ ．

类比上述推证方法，根据两角和与差的余弦公式，证明：

cosA﹣cosB=﹣2sin $\frac{A+B}{2}$ sin $\frac{A-B}{2}$ ．

10.001读作____

—What's the news about?

—People near the lake didn't allow them to________ a factory so as not to pollute the water.

下列海峡，既是两大洋又是两大洲分界线的是（    ）

阅读上面短文，然后判断句子正( A )误( B)。
     A man saw a boy standing beside a lake with a mirror (镜子).“Excuse me,” he said, “but could you tell me what you're doing?”
   “I'm fishing.”
   “With a mirror? Could you tell me how it works?”the man asked.
   “OK, but I want five dollars.”
     The man wanted to know the secret very much, so he handed the boy the money.“Now show me how it works,” he said. “Well”, the boy began, “you hold (拿) the mirror towards the water, and when a fish goes by, the sunlight in the mirror gives him a surprise. He stops and doesn't know what to do, and then you catch him at once. ”The man was surprised, “Can you really catch fish with the mirror? How many did you catch?”
   “You're the fifth today!” replied the boy.