问题
选择题
下列有关实验或操作的叙述正确的是
A．实验室可采用如图所示装置制取氨气
B．用分液漏斗从石油里分离出汽油、煤油和石蜡
C．用浓硝酸与蛋白质的颜色反应鉴别部分蛋白质
D．用碱式滴定管盛装KMnO4溶液滴定FeSO4溶液
答案
答案：C
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下列有关实验或操作的叙述正确的是
A．实验室可采用如图所示装置制取氨气
B．用分液漏斗从石油里分离出汽油、煤油和石蜡
C．用浓硝酸与蛋白质的颜色反应鉴别部分蛋白质
D．用碱式滴定管盛装KMnO4溶液滴定FeSO4溶液
答案：C
Not long before, my daughter's shoes were scratched with a knife．She burst into 36 ．I took them to the shoemaker to get them 37 ． The young apprentice （学徒） glanced at the opening and said, " 38 I can do except replace the upper．" His master looked at them and said to me, "If you 39 me, I will add more scratches on both of the shoes．" I was 40 and asked why． He explained, "As if the openings were made 41 for the sake of special style and reuse．" Two days later I found there were indeed more scratches on 42 shoe, but all the openings were patched （打补丁） by soft red leather with edges sewed by thick thread, 43 more unique and interesting than ever．I couldn't help but 44 the master's skill． Another time, my wife's sister's white blouse had been torn, leaving a large opening on the back．My wife 45 the blouse carefully, and then said, "Let me take it 46 _ and mend it．" Seeing the blouse again, I was shocked: all the torn parts had been sewed up by thin and 47 thread and they 48 a look of ice crystal （冰晶） hanging from a winter's branch． 49 , she had attached a snowman and a cabin made of flowery cotton rags onto the shirt．I 50 with praise, "It's just as beautiful as a piece of 51 !" "I was inspired by that craftsman．Patches are supposed to be 52 , but a skillful craftsman can make it take on a kind of perfection," replied my wife． Her words inspired me even more: Perfection is 53 to achieve in everything; Patches are unavoidable, so is human's life．Since you can't 54 the existence of wound, you should not expect people's 55 by exposing the wound, which reveals nothing meaningful．
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