— Tom Tim and the fist prize.
— Congratulations!
A:defeated; defeated
B:won; won
C:defeated; won
D:won; defeated
分式方程xx-1﹣2=3x-1x+2的解是( )
①拒绝利用网络进行交往,因为网络交往都是虚假的 ②提高自己的辨别能力
③增强自己的安全防范意识,不轻易泄露个人资料 ④学会自我保护,遵守网络规则
用显微镜进行观察时,被观察的生物材料必须是极薄或透明的,其原因是( )