某一变量分为下述两组:15-20,21-25,由此可以判断该变量为一连续变量。()
参考答案:错
阅读短文,判断下列句子正(T)误(F)。
I am a little fish. I live in the sea. It is dark (黑暗的) there, but I am not afraid. There are so many fish
living near me that I always have lots of friends.
I feel happy very much, because I love to swim. My mother often warns (警告) me to be careful (小心的)
because some big fish may eat me up. I know that she is right. Mother loves me and I love her, too.
短语注释: ①so…that… 如此……以致 ②warn …to do 警告……做…… ③eat up 吃(光)
( ) 1. My home is in the sea.
( ) 2. I like swimming.
( ) 3. I have many classmates.
( ) 4. If I am not careful enough, some big fish may kill me.
( ) 5. Mother and I love each other.
命题“已知x、y∈R,如果x+y≠2,那么x≠0或y≠2.”是______命题.(填“真”或“假”)