A:体液免疫
B:细胞免疫
C:自身免疫
D:非特异性免疫
如图是元素周期表中银元素的信息示意图,对图中信息理解不正确的是( )
—Jenny, would you like to go hiking with me on Sunday or Saturday?
—_______ day is OK. I am free all this weekend anyway.
关于x的一元二次方程(m﹣2)x2+2x+1=0有实数根,则m的取值范围是( )