正确答案及解析
正确答案
解析
【答案】
【考情点拨】本题考查了二元函数的混合偏导数的知识点．
【应试指导】
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学校将组织一次英语演讲比赛，打算邀请外教（John）来做评委。请你（Li Yuan）给他写一封e—mail，内容包括：?
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·告知他比赛安排（如：时间、地点等）；?
·希望他赛后进行点评；?
·期待他能接受邀请。
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A.I am free on Sunday.
B.See you then!
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E.I need a break!
F.Would you like to join us?
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Daniel:How are you doing,Linda?
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- A.见图A
- B.见图B
- C.见图C
- D.见图D
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Heahh care experts have long drawn attention to the problems of eating too much sah．There isstrong evidence that a diet high in salt can lead to raised blood pressure．Since high blood pressure is amajor factor in heart disease．it makes sense to cut down on the salt people eat．?
In the past，food contained very little salt，and people added it to their food at the table．Very fewpeople ?add ?salt this ?way ?nowadays．However，the ?salt ?content ?of processed ?foods has ?gone ?updramatically．It’s now estimated that over three．quarters of the salt in the average diet comes fromprocessed foods，eaten without our being aware of it．?
Salt is added to food partly to extend shelf-life．but more often it’s dropped in to make up for theflavor lost in the manufacturing process．This is especially true of ready meals and highly processedfoods．but it’s also true of such basic food as biscuits，soups，and even bread．Much mass—producedbread，for instance．contains so much salt．half a gram for every hundred grams of bread--that it’sofficiallv classified bv the UK government as high——salt food．Salt has to be added to the bread becausefast Droduetion cuts down the time for the flavor to develop．Without added salt，the bread would tastelike paper．?
In the UK，the government has launched a campaign to cut down on the salt people eat．The UK Food Standards Agency argues that nearly half of the UK’s population eat too much salt—9．5 9 a day onaverage．Its aim is to bring down the average t0 69 a day．The idea is to cut the salt content in 85 keyfood categories such as bread．meat．and cakes．?
?What is the passage mainly about?
-
- A.Salt and food flavor
- B.Salt and people' s lifestyle
- C.Salt and food processing
- D.Salt and people' s health
- 查看答案
Heahh care experts have long drawn attention to the problems of eating too much sah．There isstrong evidence that a diet high in salt can lead to raised blood pressure．Since high blood pressure is amajor factor in heart disease．it makes sense to cut down on the salt people eat．?
In the past，food contained very little salt，and people added it to their food at the table．Very fewpeople ?add ?salt this ?way ?nowadays．However，the ?salt ?content ?of processed ?foods has ?gone ?updramatically．It’s now estimated that over three．quarters of the salt in the average diet comes fromprocessed foods，eaten without our being aware of it．?
Salt is added to food partly to extend shelf-life．but more often it’s dropped in to make up for theflavor lost in the manufacturing process．This is especially true of ready meals and highly processedfoods．but it’s also true of such basic food as biscuits，soups，and even bread．Much mass—producedbread，for instance．contains so much salt．half a gram for every hundred grams of bread--that it’sofficiallv classified bv the UK government as high——salt food．Salt has to be added to the bread becausefast Droduetion cuts down the time for the flavor to develop．Without added salt，the bread would tastelike paper．?
In the UK，the government has launched a campaign to cut down on the salt people eat．The UK Food Standards Agency argues that nearly half of the UK’s population eat too much salt—9．5 9 a day onaverage．Its aim is to bring down the average t0 69 a day．The idea is to cut the salt content in 85 keyfood categories such as bread．meat．and cakes．?
Which of the following is classified as high—salt food by the UK government?
-
- A.Mass.produced bread
- B.Light-cooked meat
- C.Sweet biscuits
- D.Fresh vegetables
- 查看答案
Heahh care experts have long drawn attention to the problems of eating too much sah．There isstrong evidence that a diet high in salt can lead to raised blood pressure．Since high blood pressure is amajor factor in heart disease．it makes sense to cut down on the salt people eat．?
In the past，food contained very little salt，and people added it to their food at the table．Very fewpeople ?add ?salt this ?way ?nowadays．However，the ?salt ?content ?of processed ?foods has ?gone ?updramatically．It’s now estimated that over three．quarters of the salt in the average diet comes fromprocessed foods，eaten without our being aware of it．?
Salt is added to food partly to extend shelf-life．but more often it’s dropped in to make up for theflavor lost in the manufacturing process．This is especially true of ready meals and highly processedfoods．but it’s also true of such basic food as biscuits，soups，and even bread．Much mass—producedbread，for instance．contains so much salt．half a gram for every hundred grams of bread--that it’sofficiallv classified bv the UK government as high——salt food．Salt has to be added to the bread becausefast Droduetion cuts down the time for the flavor to develop．Without added salt，the bread would tastelike paper．?
In the UK，the government has launched a campaign to cut down on the salt people eat．The UK Food Standards Agency argues that nearly half of the UK’s population eat too much salt—9．5 9 a day onaverage．Its aim is to bring down the average t0 69 a day．The idea is to cut the salt content in 85 keyfood categories such as bread．meat．and cakes．?
What can be inferred about people’s use of salt in the past?
-
- A.People used salt to control blood pressure
- B.People ate much salt in their average diet
- C.People were clear about the harmful effect of salt
- D.People didn ’t eat so much salt as we do today
- 查看答案