A:①②
B:②③
C:①④
D:③④
— He plans to give a speech to raise food and clothes for the disabled next month.
— That’s great. I also want to help those children_________.
图为人体内某结构的血液情况模式图,B代表某器官或结构,A、C代表血管,箭头代表血流方向,下列叙述正确的是( )
若关于x的一元二次方程(k﹣1)x2+x﹣k2=0的一个根为1,则k的值为( )