The fire _____ at around 3a.m.local time when people were celebrating with fireworks.
I'm sorry to hear it.( )
A.broke outB.ran outC.went outD.put out
“a= -2”是“直线与互相平行”的()
在复平面内,复数(i是虚数单位)对应的点位于()
设全集,集合,,则()
当时,不等式恒成立,则实数m的取值范围是()
已知函数,则方程的实根的个数为()