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英文 高中

請問第16、17要怎麼作答

It's widely known that bees are important for our ecosystem and that they are facing increasing threats from modern agricultural practices involving pesticides. What many of us don't know, 16. (is that some industries should shoulder a bigger share of blame than they're given.) The almond industry, for instance, has quite an adverse impact on bee colonies. One potential harm to bee colonies is the stress caused by transporting them over long distances to almond orchards for the task of pollination. This transportation can be stressful for the bees, hence 17. them more vulnerable to diseases and pests. Moreover, since they're 18. having limited food sources aside from almond flowers further weakens bee colonies. Still another problem is the of honeybees to pesticides and other chemicals used in almond production. 19. 20. and One sustainable solution is to make habitats and species within almond orchards more stable. By creating various ecosystems and introducing other insects among almond trees, at least we can ensure enough food supply for bees and even lower the use of pesticides for almond trees in the long run. A 16. (A) therefore (B) however C17. (A) make A (B) made 18. (A) faced with a great increase in demand (C) looked after by beekeepers carefully (B) delivery 19. (A) cultivation 2 (C) in addition (D) for a start (C) making (D) to make (B) raised in their natural environment (D) physically removed from their habitat (C) exposure (D) restriction asant (D) particular

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英文 高中

請問B、C如何判斷?我沒有辦法把這兩個選項跟文章串起來,看不出他們有什麼關聯😭

女大考三題型 Unit 8 The Risks of Bio-terrorism In 2001 a number of US government employees and citizens died, after opening 1 letters deliberately contaminated with a deadly disease. 2 The government has responded to the threat by introducing a "Bio-Watch" system, which uses special equipment to detect unusual organisms in the atmosphere. Nevertheless, it can provide an early warning system for major towns and cities, allowing medicine to be rushed to an area under attack. 3 However, the US government is much more worried about the psychological impact, rather than the actual death toll, of a bio-terrorist attack. Any disease effectively released as a bio-weapon in a highly populated zone could cause general panic. 4 As a result of the continuing bio-terror threat, the US government is trying to make its citizens more confident that it can combat this menace. By doing so, it hopes that there will be less widespread panic. Therefore, if a major bio-attack occurs, people can take immediate action to minimize the damage. (A) This was probably the work of a mad scientist, but it signaled to all Americans that bio-terrorism was a clear and present danger. (B) This might freeze normal economic activities in the world's biggest economy center, and thus cause chaos in the global financial system. (C/Infected people can then be treated, and most will survive. DUnfortunately, this technology cannot filter the mail or prevent terrorists releasing diseases in enclosed places. 1. 2. y 3. C 4.

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自然科學 大學

想問3-9的a跟c

Problems 3-1. Explain the difference between *(a) random and systematic error. (b) constant and proportional error. *(c) absolute and relative error. (d) mean and median. *3-2. Suggest two sources of systematic error and two sources of random error in measuring the length of a 3-m table with a 1-m metal rule. 3-3. Name three types of systematic errors. *3-4. Describe at least three systematic errors that might occur while weighing a solid on an analytical balance. *3-5. Describe at least three ways in which a systematic error might occur while using a pipet to transfer a known volume of liquid. 3-6. Describe how systematic method errors may be detected. *3-7. What kind of systematic errors are detected by varying the sample size? 3-8. A method of analysis yields masses of gold that are low by 0.4 mg. Calculate the percent relative error caused by this result if the mass of gold in the sample is (a) 500 mg. (b) 250 mg. V(c) 125 mg. (d) 60 mg. 3-9. The method described in Problem 3-8 is to be used for the analysis of ores that assay about 1.2% gold. What minimum sample mass should be taken if the relative érror resulting from a 0.4-mg loss is not to exceed *(a) -0.1%? (b) -0.4%? (c) -0.8%? (d) - 1.1%? 3-10. The color change of a chemical indicator requires an overtitration of 0.03 mL. Calculate the error if the total volume of titrant is percent relative (a) 50.00 mL. (c) 25.0 mL. 3-11. A loss of 0.4 mg of Zn occurs in the course of an percent relative analysis for that element. Calculate the error due to this loss if the mass of Zn in the sample is *(b) 10.0 mL. (d) 30.0 mL. 190 (c) 188 (d) 4.52 x 103 4.63 x 103 4.53 x 10 ³ √6 *(a) 30 mg. (b) 100 mg. *(c) 300 mg. (d) 500 mg. 3-12. Find the mean and median of each of the following sets of data. Determine the deviation from the mean for each data point within the sets, and find the mean devi- Vation for each set. Use a spreadsheet if it is convenient. *(a) 0.0110 0.0105 (b) 24.53 0.0104 24.68 24.81 24.77 39.61 862 (f) 850 MA 3-13. Challenge Problem: Richards and W the molar mass of lithium and colle data. 24.73 Experiment 1 2 3 4 5 6 194 447 X 10 7 448 X 107 4.58 X 10 (a) Find the mean molar t workers. (b) Find the median molar ma (c) Assuming that the cam molar mass of lithium is the absolute ertor and of the mean value demi Willard. (d) Find in the chemical ues for the molar mus since 1910, and ag a table or spreadshera 1817 given in the a Richards and Willd. Com mass versus year to la of lithium has chang Suggest possible abruptly about 18 ant de (e) The incredibly deals Richards and W that major changes will occur. Disc calculation in pat (f) What factors ha since 1910? (g) How would you mass? 6See Chapter 2 of Applications of Microsoft Excel in Analytical Chemistry, 4th ed., for information about statistical 7T. W. Richards and H. H. Willard, J. Am. Chem. Soc., 1910, 32, 4, DOI: 10.1021/ja01919a002. built-in statistical functions. "Answers are provided at the end of the book for questions and problems marked with an asterisk The I of ₂ or inc rce of able vas error c often in individu ate resul data in rtainties. dimensio andom e analysts The result

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