设计承包商编制的设备设计计划的必要附件包括（）。 A.设计合同 B.项目设计数据 C

“春蚕到死丝方尽”，这里“丝”的主要成分是（　　）

A．蛋白质

B．维生素

C．棉纤维

D．油脂

下列做法中，不会对人造成危害的是（　　）

A．用食醋熏蒸，进行室内消毒

B．在食盐中添加工业用盐（NaNO₂）

C．在蒸馒头的面团中加一点烧碱

D．在不通风的浴室内使用燃气热水器

根据课文内容用适当的词填空，使短文完整。(一空一词)

    Not long ago, a girl called Daisy took a magic 1.______ around the world, riding a

flying chair. First, she came to Tibet in China to visit antelopes. But to her great

2._____, she could only see mountains and people.

    Then an antelope told her 3.______ that they were being killed 4.______ large numbers

by humans for their wool to make clothing. And they might be 5._______ forever in three

years. Then the flying chair took Daisy to Zimbabwe, 6.______ wildlife was properly

protected. Daisy was glad to learn that farmers there were not killing the animals at

will as they 7._____ to. Only a certain number of the animals were set to be 8.______ for

fee by the government, 9.______ not only saved the animals but benefited the farmers as

well.

    At last, Daisy flew to a 10.______ rainforest. There she was puzzled to see a monkey

11.______ (rub) a millipede insect over its body. Then the monkey told her the insect

contained a 12._______ drug which affected mosquitoes and 13._______ rubbing it over the

body it could 14._______ itself from mosquitoes. Now Daisy was amazed and excited to find

in fact the forest 15._______ a lot of precious things people can make use of. So

protecting nature really means much to our humans.

在实际生产中，反应2SO₂+O₂2SO₃(g)；△H<0，应选择的适宜条件是（   ）

A．高温、高压、催化剂

B．低温、高压、催化剂

C．高温、低压、催化剂

D．适当温度、常压、催化剂

透明