——Do you know that there are many different _______animals in the zoo?——Yes, I do. And I also know that some of them are ________scaring.
A:kinds of; kind of
B:kinds of; kinds of
C:kind of; kinds of
D:kind of; kind of
下列反应能生成水且属于分解反应的是____ A.氢气的燃烧 B.水的通电分解 C.双氧水的分解 D.____ .
下列关系式:(1)y=-x;(2)y=2x-1;(3)y=2x;(4)y=kx(k>0).其中y是x的反比例函数的有( )