一元二次不等式$a{x}^2+bx+2>0$的解集是$\left(-\frac{1}{2},\frac{1}{3}\right)$，则$a+b$的值是（   ）

在卫星云图上，绿色表示（　　）

下面的标题运用了什么修辞手法？按顺序填空，下列几组答案中正确的一项(    )

①《手术台就是阵地》    ②《蟋繂的住宅》

③《沙漠里的船》        ④《把牢底坐穿》

下列各分子中所有原子都满足最外层为8电子结构的是（   ）

     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?