若命题“$\exists x_0\in R$，使得x₀²+mx₀+2m-3<0”为假命题，则实数m的取值范围是(     )

选词填空。

        restaurant        park           supermarket

功率大小的三种比较方法：

（1）在相同时间内，比较做功的多少，做功越____ 的物体，功率越大；

（2）在完成相同功的条件下比较所用时间的长短，所用时间越____ 的物体，功率越大；

（3）做功的多少和所用时间都不同的情况下，通过公式 ____ 进行比较。

     Tom and Mike are good friends. They are good with children. They want to find jobs in summer vacation. This Friday Tom tells Mike that Sunson School Trip needs teachers to help with sports, music and computer. Mike is glad to know that.
    Tom can play basketball, volleyball, and he can swim. Mike can play the violin, the trumpet, the drums and the guitar, and he can swim,too. Tom and Mike like computers very much. Can they join Sunson School Trip?

下图所示地区地壳活跃，板块运动明显，由图可得出的正确推论是（    ）