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duyl817
2 năm trước
Biết rằng khi cho muối ăn vào nước ta được dung dịch muối có thể tích khác với thể tích nước đã sử dụng với đầy đủ các dụng cụ và hóa chất hãy trình bày cách tạo ra chính xác nhất a:50 ml dung dịch có chứa 2 gam muối ăn b: 50 gam dung dịch có chứa 2 gam muối ăn
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Có bạn nào nuôi mèo không ạ 4 hôm trước mình có mua một bé mèo con, khi về nhà có tình trạng này mong bạn tư vấn giúp: Ngày 1: Bé về nhà ăn một ít pate, ngủ nhiều, tối cũng ăn được ít pate, phân đi bình thường. Ngày 2: Bé ọe ra nước bọt, không chịu ăn gì, buổi tối nôn ra giun đũa, mình lập tức đưa bé đi xổ giun và cho uống men tiêu hóa. Bé vẫn không chịu ăn, chỉ uống nước. Ngày 3: Mình thử cho bé ăn ít gà luộc xé nhỏ, bé đang ngủ ngửi mùi dậy ăn luôn, ăn được kha khá, nhưng bé đi cầu thì bị tiêu chảy, buổi tối lại nôn một bãi giun con và chỉ uống nước. Ngày 4: Sáng dậy mình đi xúc cát thì thấy bé vẫn bị tiêu chảy, cũng chỉ uống nước.Mình thử đi mua ít ức gà về cho bé ăn cả luộc cả sống thì bé vẫn không chịu ăn dù hôm qua cũng ăn bth.Bé nôn ra bãi nước bọt trắng 2-3 lần. Bốn ngày qua bé đều ngủ li bì, rất ít hoạt động, cả cần câu mèo thì chơi chỉ được một lúc. Thấy mn nói mèo con mới về nhà thì lạ nhà nên thường bỏ ăn, mà bé nhà mình cũng vừa xổ giun nên cứ chờ vài ngày bé đói sẽ ăn lại bình thường, nhưng mình vẫn lo quá, mong bạn giúp mình nên làm gi ạ.

IV. Rewrite the sentences so that they are nearest in meaning to the sentence printed before them. 35 I was surprised at how easy he was to talk to. I hadn’t expected 36 It’s almost nine months since I stopped subscribing to that magazine. I cancelled 37 My decision to get up and dance coincided with the band’s decision to stop playing. When 38 After seeing the film for himself, my father has stopped criticising it. Since 39 John hasn’t done any revision since spring term. The last time V. Choose the correct sentence from the four options a, b, c or d 40 I/ couldn’t/ see/ more/ a few/ feet/ front/ me/ because/ the/ snow. a. I couldn’t see more a few feet in front of me because of the snow. b. I couldn’t see more a few feet in front of me because the snow. c. I couldn’t see more than a few feet in front of me because the snow. d. I couldn’t see more than a few feet in front of me because of the snow 41 A lot of/ people/ be/ injured/ the/ earthquake. a. A lot of people were injured in the earthquake. b. A lot of people were injured on the earthquake. c. A lot of people were injured at the earthquake. d. A lot of people were injured for the earthquake. 42 If/ there/ be/ fire/ in/ your house, call/ 114 a. If there is a fire in your house, to call 114 b. If there is a fire in your house, calling 114 c. If there be a fire in your house, call 114 d. If there is a fire in your house, call 114 43 The/ volcanic eruption/ be/ so destructive/ that/ many lives/ be threatened a. The volcanic eruption was so destructive that many lives were threatened b. The volcanic eruption is so destructive that many lives are threatened c. The volcanic eruption be so destructive that many lives are threatened d. The volcanic eruption be so destructive that many lives were threatened 44 What/ you/ do/ if/ there/ tornado/ in/ your area? a. What would you do if there is a tornado in your area? b. What would you do if there was a tornado in your area? c. What would you do if there were a tornado in your area? d. What would you do if there has been a tornado in your area? 45 We/ should/ people/ try/ time/ to/ evacuate/ predict/ to/ in/ earthquake a. We should try to predict earthquake to evacuate people in time. b. We should predict to try earthquake to evacuate people in time. c. We should predict to try earthquake in evacuate people to time. d. We should try to predict earthquake in evacuate people to time. VI. Read the passage and choose the letter A, B, C or D to answer these following questions Red Alert: Volcanoes \n Volcanoes can be fun to learn about. It can be neat to watch them erupt. But if you live near a volcano, you know that they are dangerous! \n An eruption can like an explosion. Rock and lava can throw up into the air. Streams of red hot lava quickly run down from the peak of the volcano. The air is filled with deadly gases. These things can put many lives in danger. Scientists have learned that there are many things that they can study to help them tell when an eruption might happen. They can study the movements of the ground. When a volcano is about to erupt, the ground will often move just like it does during an earthquake. Scientists can also measure the gases that come out of a volcano. Most volcanoes emit gases all of the time. More gases are let out as the volcano gets closer to erupting. They can also study the way the land and water around the volcano. Scientists can read these signs and warn people of danger. They may not realize it, but their work helps to keep people safe! \n 46 In the passage, a volcanic eruption is compared as ............... a. an explosion b. an exploration c. a bomb d. a danger 47 ............... can come out from a volcanic eruption. a. Rock b. Lava c. Gases d. All above 48 .......... can study many things to predict when an eruption might happen. a. Economists b. Scientists c. People d. Biologists 49 There are ............ ways for studying to estimate the time an eruption might happen. a. 1 b. 2 c. 3 d. 4 50 When an eruption is going to happen, ........... a. the ground moves as it does during an earthquake. b. the gases don't come out of it more than usual. c. only the water around it changes. d. the ground moves slowly and weakly.

I. Choose the word whose main stress pattern is not the same as that of the others. 1 a. industry b. nature c. interact d. climate 2 a. typhoon b. tropical c. debris d. document 3 a. animal b. destroy c. erupt d. exploit 4 a. documentary b. preparation c. scientific d. photography 5 a. eruption b. science c. destroy d. volcano II. Choose the word or phrase (a, b, c or d) that best fits the blank space in each sentence. 6 The facsimile ............ by Alexander Bain in 1843 a. is invented b. was invented c. invented d. has been invented 7 First, fry the onions ............ add the potatoes. a. than b. then c. after d. before 8 He ............ a prize in the competition last week. a. win b. won c. was won d. has win 9 Who ............ the company? a. goes b. walks c. jogs d. runs 10 ............ is an instrument for making sounds louder. a. Loudspeaker b. Recorder c. Facsimile d. Radio 11 The doctor told me ............ more fresh fruit. a. eat b. to eat c. eating d. ate 12 Can you___________my bike? a. adjust b. use c. fix d. A & B 13 Coffee was known in Europe ............ “Arabian wine”. a. as b. like c. the same d. unlike 14 The information ............ for future use. a. stores b. stored c. is stored d. are stored 15 I saw a ............ flying overhead a. train b. helicopter c. conveyor belt d. coach 16 This beautiful picture ............ by Mary. a. is drawn b. is drew c. is draw d. is drawing 17 Don’t (touch) the paint! - It’s still wet (Choose the closest meaning) a. put paint on something to change the color b. take something c. do a job with something d. put your hand or finger on something 18 I warned him ............ too close to the fire. a. didn’t go b. not going c. no going d. not to go 19 ............ is a pen that has a very small ball at the end a. Ball-point pen b. Fountain pen c. Pencil d. Crayon 20 Tobacco is taxed in most countries, (along with) alcohol. (Choose the closest meaning) a. in the same way as something b. but not something c. for example d. including 21 James picked up the ............ and said “Hello!” a. vacuum b. printer c. telephone d. fax machine 22 Children, please (behave)! (Choose the closest meaning) a. do and say the right things b. do something c. do what somebody tells you to do d. move on your legs, but not run 23 We now toast bread ............ a toaster on the table. a. by b. with c. from d. in 24 Which ............ shall I press to turn the radio on? a. plug b. roll c. roller d. button 25 Don’t sit ............ the sun too long. a. in b. on c. over d. among III. Choose the underlined word or phrase (A, B, C or D) that needs correcting. 26 Venus (A)approaches (B)the Earth more closely than (C)any other planet (D)is. a. approaches b. the Earth c. any other d. is 27 (A)The amounts of oxygen and nitrogen in the air (B)almost always remain (C)stable, but the amount of water vapor (D)vary considerably. a. The amounts of b. almost always c. stable d. vary 28 The American (A)frontiersman, politician, and soldier Davy Crockett is one of the (B)most popular (C)of American (D)hero. a. frontiersman b. most c. of d. hero 29 (A)The students suggested (B)buying flowers (C)for the teachers (D)in the Teachers’ Day. a. The students b. buying c. for d. in 30 No one (A)have (B)solved (C)such (D)a difficult problem a. have b. solved c. such d. difficult 31 (A)During their (B)meat, they discussed what (C)to do (D)at the weekend a. During b. meat c. to do d. at 32 (A)If you (B)write the essay (C)careful, you (D)will get good mark. a. If b. write c. careful d. will 33 Dietitians urge people (A)to eat (B) a banana a day to get (C)potassium enough in (D)their diet. a. to eat b. a banana c. potassium enough d. their diet 34 Woody Guthrie (A)has written (B)thousands of songs (C)during her lifetime, many of (D)which became classical folk songs. a. has written b. thousands c. during d. which

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