下列诗句与民谣中，反应新疆气候特点的是（  ）

在三角形ABC中，角A、B、C的对边分别为a，b，c，且满足$\frac{a}{6}$=$\frac{b}{4}$=$\frac{c}{3}$，则$\frac{\sin 2A}{\sin B+\sin C}$=（　　）

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　　Today is Sunday. Mike and Peter 1 go to school. Listen! They are talking about the life  2 in the room." 3 will the world be like? "Peter asks."I think that the world will be a 4  place to live in. And we will 5 machines and robots at home. They will help us do lots of 6  , "says Mike. "The robots will help  7 cook dinner, clean the houses and  8 old people. I think there will be a kind of medicine(药)  9  it can make us live more than 100 years, "Peter says."What will you do then? "says Mike."Then I will  10  my great-grandchildren(曾孙)to the moon, "says Peter. "The moon? I will go to the Mars(火星)with my wife, "says Mike.