Cho \(\partial< 90^o\)
Biết \(\cos\partial+\sin\partial=\frac{1}{5}\) Tính \(cot\partial\)
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NL
0
14 tháng 12 2019
Kiến thức: Từ vựng, từ trái nghĩa
Giải thích:
partial (adj): một phần
whole (adj): toàn bộ halfway (adj): nửa chừng
half (n): một nửa effective (adj): hiệu quả
=> partial >< whole
Tạm dịch: Tôi chỉ có thể đề xuất một giải pháp một phần cho cuộc khủng hoảng trong công ty.
Chọn A
HC
5
B
10 tháng 2 2023
others.( 1 pt)
1. A. action B. national C. partial D. question
2. A. tidal B. sight C. describe D. cinema
3. A. connect B. comfort C. computer D. contest
4. A. cough B. though C. rough D. tough
5. A. pleased B. erased C. increased D. amused
II. Choose the word or phrase ( A,B,C or D) that best fits the blank space in each sentence. ( 2pts)
1. - Mary: “Is 11 o’clock alright?” - Tom: “______.”
A. Yes, that’s fine(tham khảo c1 bài II) B. No, I don’t want to go C. Wait a minute D. Sounds interesting
2. Typhoons, floods or droughts can easily ______ a harvest.
A. finish B. destroy C. provide D. defeat
3. You should pay ______ to what the instruction is saying.
A. attendance B. intention C. convention
D. attention
4. My friends usually enjoy my ______ of humor.
A. sense B. kind C. means D. form
5. - Mother: “Could you do me a favor?” - Kate: “______.”
A. No, thanks. I’m fine B. Yes, that’s kind of you C. Yes, sure D. Yes, thank you
6. Practising ______ English anywhere you can is a way to better your speaking skill.
A. speak B. speaking C. to speak D. for speaking
7. Soak some old newspapers in a ______ of water overnight.
A. pair B. bunch C. bucket D. tube
8. Mrs. Thanh: “______ you give the book to me, please?” - Mai: “Of course.” .
A. Will B. Shall C. Do D. Should
9. The winners are the first ones ______ a fire.
A. make B. makes C. making D. to make
10. Do you know the man………………… met our teacher yesterday?
A. who B. whom C. which D. whose
III. Give the correct tense or form of the verbs in brackets.( 2pts)
1. How many times have you been….you (1.be) to London this year? |
2. The two girls (2.play)playing chess over there are my classmates. |
3. We must take an umbrella. It (3.rain).is going to rain |
4. The guests (4.arrive)arrived while I (5.still / cook).was still cooking |
5. The rice-cooking festival (6.hold)held every two years. |
6. I often (7.climb)climbed trees when I was a little girl. |
7. Two miles (8.be)is enough for her to go jogging every morning. |
8. I’m very bored. My mother always (9.complain)is always complainingabout her housework. |
9. Fred would like (10.admit)to be admitted to the college. |
IV. Choose the word or phrase ( A,B,C or D) that best fits the blank space in the passage. ( 1,5pts)
Have you ever been to Britain? I’ve dreamed of going there (1) ______ I was a little girl and finally, in the spring of 2012, it happened. I was there three weeks and (2) ______ much of that time soaking up the culture, history, and scenery of this incredible island. I visited several districts in England, Wales and Scotland and even (3) ______ a site trip to Ireland. Every place I went to seemed to be more interesting and more beautiful than the last.
The tour I was with began in London. Of all the sights I saw there, the Tower of London was the most (4) ______. The Tower is a building complex of incredibly rich history.
Also on the Thames are the Houses of Parliament and, of course, the clock tower housing “Big Ben”. I saw so many landmarks I can hardly remember them all. Although it was just a glimpse of London I did, (5) ______, get a chance to see all the most famous places.
After a couple of days in London we traveled to the south of England stopping to visit Stonehenge. If you don’t know about Stonehenge there are a couple of links on my links page that will (6) ______ you to sites that can fill you in.
1. A. for B. while C. since D. because
2. A. spent B. took C. did D. used
3. A. did B. got C. spent D. made(tham khảo c3 bài đọc)
4. A. interesting B. interested C. interest D. interestingly
5. A. at first B. at all C. at least D. at that
6. A. reach B. take C. make D. send
V. Read the passage and answer the questions.(1pt)
Every child in England must receive full time education from the age of five to sixteen. Many parents send their children to state schools where the tuition and the equipment, textbooks and exercise books are free. About 5% of children go to fee-paying school. Under the old system, children attended primary school (from five to eleven) which was followed by a secondary school course (from eleven to fifteen or over. At eleven every child had to sit for the eleven–plus examination. It consisted of tests in English, Arithmetic and intelligence tests. Those with the highest marks (about 20% of the children) went to grammar school. The others went to technical school.
Questions:
1. When do English children start and finish their full time education?
……………… Every child in England must receive full time education from the age of five to sixteen. …………………………………………………………………
2. Which schools do many parents send their children to?
…………………Many parents send their children to state schools……………………………………………………
3. Do they have to buy textbooks and exercise books at state schools?
………………No, they don't………………………………………………………………
4. What did every child have to do at eleven under the old system?
………………… At eleven every child had to sit for the eleven–plus examination. ……………………………………………………
5. Who were allowed to go to grammar school?
……………………Students at eleven with the highest marks (about 20% of the children) went to grammar school…………………………………………………………
VI. Rewrite each sentence, beginning as shown, so that the meaning stays the same.(1,5pts)
1. I sent my friend a letter in London last week.
ð A letter ______was sent to my friend in London (by me) last week________
2. I last saw him when I was a student.
ð I haven’t _______seen him since I was a student______________
3. “Don’t forget to bring your passports with you when you go abroad.”
ð She reminded ____me to bring my passports with me when I went abroad______________________
4. Smoking is not allowed in the ward.
ð Would you _______mind not smoking in the ward_____________________?
5. He failed the exam because of his laziness.
ð Because he_____was lazy, he failed the exam__________________.
VII. Use the words or phrases given to complete the sentences.(1pt)
1. Instead / reuse / plastic bags / we / use / cloth bags.ð_______Instead of reusing plastic bags, we use cloth bags__________________________________________.
2. Will / you / have / look / house / me / while / I / be / holiday?
ð_______Will you have a look at my house while I am on holiday?__________________________________________.
3. We / hope / give / more / green / color / town / and / earn / money / group.
ð _________We hope to give more green color to town and earn money for our group____________________________________________.
4. “Friends of the Earth” / be / organization / protect / planet.
ð _____"Friends of the Earth" is an organization protecting planet__________________________________________________.
5. It / brave / him / jump / river / save / child.
ð_____It was brave of him to jump into the river to save the child__________________________________________________.
H
22 tháng 2 2023
a) $Fe + 2HCl \to FeCl_2 + H_2$
b) Theo PTHH : $n_{FeCl_2} = n_{Fe} = \dfrac{11,2}{56} = 0,2(mol)$
$m_{FeCl_2} = 0,2.127 = 25,4(gam)$
c) $n_{H_2} = n_{Fe} = 0,2(mol)$
$V_{H_2} = 0,2.24,79 = 4,958(lít)$
d) $RO + H_2 \xrightarrow{t^o} R + H_2O$
Theo PTHH : $n_{RO} = n_{H_2} = 0,2(mol)$
$\Rightarrow M_{RO} = R + 16 = \dfrac{16}{0,2} = 80$
$\Rightarrow R = 64(Cu)$
CTHH oxit : $CuO$
$n_{Cu} = n_{H_2} = 0,2(mol) \Rightarrow m_{Cu} = 0,2.64 = 12,8(gam)$
19 tháng 2 2019
D
A. Half: một nửa
B. Halfway: nửa chừng
C. Effective: hiệu quả
D. Complete: hoàn toàn, hoàn thành
Partial : một phần>< Complete: hoàn toàn, hoàn thành
Tạm dịch: Tôi chỉ có thể đưa ra một phần giải pháp cho sự khủng hoảng của công ty.
12 tháng 10 2019
Kiến thức: Từ vựng, từ trái nghĩa
Giải thích:
partial (a): một phần
half: một nửa halfway: nửa đường
effective (a): hiệu quả complete (a): hoàn toàn, hoàn thành
=> partial >< complete
Tạm dịch: Tôi chỉ có thể đề xuất một giải pháp một phần cho cuộc khủng hoảng trong công ty
Chọn D
\(\hept{\begin{cases}cosa+sina=\frac{1}{5}\\sin^2a+cos^2a=1\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}cosa=\frac{1}{5}-sina\\sin^2a+\left(\frac{1}{5}-sina\right)^2=1\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}cosa=\frac{1}{5}-sina\\50sin^2a-10sina-24=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}sina=-\frac{3}{5}\left(l\right)\\sina=\frac{4}{5}\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}cosa=\frac{4}{5}\\cosa=-\frac{3}{5}\end{cases}}\)
Vì \(a< 90^o\) nên \(\hept{\begin{cases}sina\ge0\\cosa>0\end{cases}}\)vậy không tìm được góc thỏa bài toán.