下列措施不合理的是 A.用SO2漂白纸浆和草帽辫 B.用硫酸清洗锅炉中的水垢 C

题型:选择题

问题:

下列措施不合理的是

A.用SO2漂白纸浆和草帽辫

B.用硫酸清洗锅炉中的水垢

C.高温下用焦炭还原SiO2制取粗硅

D.用 Na2S作沉淀剂,除去废水中的Cu2+和Hg2+

考点:沉淀溶解平衡
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用“二分法”求方程2x+3x-7=0在区间[1,3]内的根,取区间的中点为x0=2,那么下一个有根的区间是(    )。

题型:选择题

我国从2009年6 1日起实施了一部重要法律,该法突出强调了“全程监督管理”,确保食品安全。该法律的实施,有利于更好抱保护公民的[ ]

A.生命健康权

B.监督权

C.荣誉权

D.人身财产安全权

题型:选择题

Plants are very important living things. Life could not go on if there were no plants. This is because plants can make food from air,water and sunlight. Animals and man cannot make food from air,water and sunlight. Animals get their food by eating plants and other animals.Therefore animals and man need plants in order to live.This is why we find that there are so many plants around us.

If you look carefully at the plants around you,you will find that there are two kinds of plants:flowering plants and non-flowering plants.

Flowering plants can make seeds(种子). The seeds are protected by the fruits. Some fruits have one seed, some have two, three or four, and some have many seeds. But a few fruits have no seeds at all. An example of a fruit without seeds is the banana fruit. Most non-flowering plants do not grow from seeds. They grow from spores(胚芽). Spores are very small. Some spores are so small and light that they can float in the air. We may say that spores are quite the same as seeds. When these spores are all on wet and shady places, they usually grow into new plants.

72. The main idea of the first paragraph is that ______.

A. plants are important for life             B. plants cannot grow without air

C. there are many plants in the world      D. we can not live without water

73. Plants can make food from______.

A. flower, water and air                                        B. water, sunlight and air

C. air, water and soil                                                       D. air, sun and light

74. What can we infer from the passage ?

A. Of all living things animals are most important 

B.Spores are seeds

C. All fruits of flowering plants have seeds  

D.Without plants, man will die out

75. This passage may be taken from______.

A. a medicine book                      B. a novel

C. a science magazine                   D. an experiment report

题型:选择题

在食管癌的根治性放射治疗中,()是常见并发症

A.食管狭窄

B.气管食管反应

C.放射性肺炎

D.肺纤维化

E.以上都是

题型:选择题

生育保险待遇包括()

A.生育医疗费用

B.住院伙食补助费

C.交通食宿费

D.生育津贴

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