题干

通过实验研究温度对a、b、c三种酶活性的影响,结果如表所示.下列说法错误的是(  )

温度

酶种类

40℃

30℃

20℃

10℃

a酶的相对活性(%)

75

95

65

40

b酶的相对活性(%)

25

97

60

15

c酶的相对活性(%)

90

50

25

10

A:a酶和b酶的最适温度为30℃左右

B:不论温度多少,酶的用量一定会影响实验结果

C:该实验中,自变量有两个,分别为温度和酶的种类

D:三种酶中较适宜高温环境的是c酶

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B

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    If you thought helicopter parents were too much, wait till you learn about “lawnmower (割草机) parents”. These are the next generation of helicopter parents, who take over-parenting to the next level. Rather than staying overhead in the air, these parents actively prepare the way for their children to succeed, cushioning every bump along the way.

    Their goal is to create a soft, even surface onto which their child will proceed, free from harm and worry. They get involved before problems reach their child, sometimes even going to immoral lengths, such as writing college papers for a child who's running out of time.

    One teacher told the Irish Times: “These days you would often hear from a mother or father insisting their child be put in the top math class, for example. Self-esteem (respect) is the buzzword (popular word). They feel it would harm their child's confidence. The irony is their self-esteem would be damaged far more by sending them into a class where they can't catch up with others.

    It's not children who are out of control. It's parents. There will come a point when these children won't have parents on which to depend, and then how are they going to function? It's frightening, too, to imagine these children becoming adults and attempting to raise families of their own. They would hardly be capable of teaching independence, confidence, work ethic, and discipline to their own children if they've never learned it themselves.

    At the end of the TIME article, Gibbs shared a wonderful quote from writer D.H. Lawrence, written in 1918: “How to begin to educate a child. First rule: leave him alone. Second rule: leave him alone. Third rule: leave him alone. That is the whole beginning.