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【简答题】
Benjamin Franklin and his inventions Benjamin Franklin was a very talented man. He invented man yuseful things. We still use some of them nowadays. In the 1740s Franklin invented the Pennsylvania Fireplace. It worked like a normal fireplace but it created more heat than a normal fireplace. People liked the Franklin Stove, as it is also called, but they only used it as a heater and not to cook hot food and drinks. Franklin was also very popular for his bifocals — a wonderful type of glasses. He needed glasses to help him see things far away and close to him. One pair of glasses only helped one of these problems, so Franklin needed to carry two pairs of glasses. One day, he got tired of always changing glasses, so he decided to put two lenses into one pair of glasses. The top lens helped him to see far away, and the bottom lens helped him to see things which' were close to him. He c alled this new type of gl a ss bifocals. Frank l in also invented the ligh t ning rod. This was a mental sick put on houses, barns or other b uildings from fire , heavy sto r ms, light ni n g hit this rod and not the building. This invention saved many buildings from fire. Unfortunately, F ranklin got an electric shock when he was doing this experiment. He did not patent any of the items he invented. A patent is a law which m e ans the inventor protects the use of his or her invention.When you patent your invention,other people cannot produce or use your invention without your agreement .Ben thought his ideas should be used to improve the lives of everyone
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参考答案:
举一反三
【简答题】白醋(含3%-5%的醋酸)是常用的调味品.现有4%的白醋500g,该溶液中含溶质醋酸______g;若再加水500g稀释后所得溶液溶质醋酸的质量分数为______.
【单选题】下面程序输出结果是System.out.println('2'+ '2');
A.
22
B.
4
C.
0
D.
100
【判断题】漳州水仙雕刻水养是我国水仙观赏的一大特点,其目的是提早开花,并能造型增加观赏性。
A.
正确
B.
错误
【单选题】执行下面程序输出结果正确的是()。 public class Test{ public static void main(String args[]){ System.out.print(100%3); System.out.print(","); System.out.print(100%3.0); } }
A.
1,1
B.
1,1.0
C.
1.0,1
D.
1.0,1.0
【多选题】以下属于客房部减量做法的有
A.
减少使用塑料品和塑料包装材料
B.
改进便器抽水装置的设计,有效控制便器的用水量
C.
减少客用布件的更换
D.
对一些客人不常用的用品不作为正常供应品在客房内配置
【简答题】白醋(含3%-5%的醋酸)是常用的调味品。现有4%的白醋500g,该溶液中含溶质醋酸_______g;若再加水500g稀释后所得溶液溶质醋酸的质量分数为_______。
【单选题】在卫生理化检验实验室中,常用浓硝酸的比重为
A.
ρ20=1.67g/ml
B.
ρ20=1.42g/ml
C.
ρ20=1.18g/ml
D.
ρ20=1.84g/ml
E.
ρ25=1.68g/ml
【单选题】食品安全中常用的GRAS指:
A.
天然的
B.
有轻微毒害的
C.
化工合成但可以安全使用的
D.
公认为安全的
【判断题】漳州水仙雕刻水养是我国水仙观赏的一大特点,其目的是提早开花,并能造型增加观赏。
A.
正确
B.
错误
【单选题】下面程序段的输出结果是 int a = 2; System.out.print( a++); System.out.print( a); System.out.print(++a);
A.
333
B.
334
C.
234
D.
233
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