A:y=﹣2x+1
B:y=﹣x2﹣1
C:y=(x+1)2﹣1
D:y= 1x
There will a new library in our school.
He won the match because he took the advantage of his height.
采用下列哪一组方法,可以依次解决①~④中的遗传问题( )
①鉴定一只白羊是否纯种 ②在一对相对性状中区别显隐性
③不断提高小麦抗病品种的纯合度 ④检验杂种F1的基因型.