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问题 选择题

除去下列物质中的杂质（括号内为杂质），所用试剂和方法不正确的是[ ]

物质（杂质） 除杂质所用试剂和方法 
A.NaCl固体（泥沙） 加水溶解、过滤、蒸发
B.FeCl2溶液(CuCl2) 加入过量铁粉、过滤
C.CO气体（CO2气体） 通入NaOH溶液洗气
D.Fe (Fe2O3) 加入稀盐酸、过滤
答案

答案：D

单项选择题

甲、乙两人各有钱若干元，若甲给乙24元，二人钱数相等；如果乙给甲30元，则甲的钱数是乙的3倍。则甲原来有多少钱

A．154

B．132

C．108

D．84
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单项选择题

(一) Today our knowledge of food and what it does for our bodies are far more advanced than that of the old times. Now we know about vitamins and how each kind of vitamin helps in the growth of a particular, the food that we eat will take care of our body and so there is no need to take any kinds of vitamins unless our doctor tells us that our bodies are short of something which can be supplied by them. Generally speaking, everything we eat does some good to our body. But if we eat too much of one kind of food and pay too little attention to others, we may have too much of one kind and not enough of others. Then we may be in trouble. We are often told that we must eat some meat at each meal in order to get the necessary proteins. That is only partly true, for proteins are not found only in meat. We can also get them from some vegetables. The best advice about what to eat is that we should eat all kinds of food but never too much of any.

Which of the following statements is TRUE______

A．All kinds of food are good to our health no matter how much we eat.

B．Meat is the best food of all.

C．Too much of any kinds of food is bad to one’s health

D．Vitamins are more useful than natural food.
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