Looking back on my childhood. I am convinced that naturalists are born and not made. Although we were brought up in the same way, my brothers and sisters soon abandoned their pressed flower
An important question about eating out is who pays for (支付) the meal. If a friend of yours asks you to have lunch with him, you may say something like this, “I’m afraid it’ll have to be so
，函数
（
），
，使得
成立，则实数
的取值范围是
B．
C．
D．
