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    Do you dream of being a reporter? Are you a good English writer who loves the news? We're looking for 100 students from around the world. They will join the BBC Kid Reporter team for the 2015～2016 school year.

    In the past, BBC Kid Reporter have:

★Interviewed leaders and other people.

★Written news stories for BBC For Kids.

★Talked about their work on television.

    Next year, our team will continue to report local news stories for BBC For Kids magazine and bbcforkids.com.

How to Enter

    Visit bbcforkids.com and fill in the entry form(报名表). Be sure to read the rules and share them with your parents who must sign(签名) your form. Entries must be done by June 19, 2015.

You must be over 13 years old。 Good luck!

方程组$\left\{\begin{array}{c}x+y=1\\ y+z=2\\ z+x=3\end{array}\right.$的解是____ 

金鱼草的花色由一对遗传因子控制，AA为红色，为粉红色，aa为白色，红花金鱼草与白花金鱼草杂交得F₁，F₁自交产生F₂。下列有关F2个体的叙述错误的是(　　)

如图，▱ABCD中，AB＞AD，AE，BE，CM，DM分别为∠DAB，∠ABC，∠BCD，∠CDA的平分线，AE与DM相交于点F，BE与CM相交于点N，连接EM．若▱ABCD的周长为42cm，FM=3cm，EF=4cm，则EM= ____cm，AB= ____cm．