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Viết bài văn nghị luận suy nghĩ về trách nhiệm của em đối với người yếu thế trong xã hội

Viết công thức Lewis khả dĩ nhất cho các phân tử và ion sau, bao gồm tất cả các cấu trúc cộng hưởng AlI3, CS2, HCOOH, COCl2, ClO3 -, NO3 -, H2S, NO2, ClO4 -, OCN- (ion xianat, nguyên tử C trung tâm) CNO- (ion isoxianat, nguyên tử N trung tâm), PO4 3-, N2O, BeCl2, AsF5, AlCl4 -. 3-4 chất đầu mong...

Hỗn hợp A gồm 2 axit cacboxylic no đơn chức mạch hở X, Y có công thức lần lượt là CnH2nO2 và CmH2mO2 (n+2=m). Cho a gam hỗn hợp A tác dụng với lượng dư dung dịch NaHCO3 thì thu được 6,72 lit CO2. Đốt cháy hoàn toàn a gam A rồi dẫn toàn bộ sản phẩm chỉ gồm CO2 và hơi nước qua bình 1 đựng P2O5...

Đốt cháy hoàn toàn hợp chất hữu cơ (X) đơn chức cho CO2 và H2O; cho 27,45g (X) tác dụng hoàn toàn vừa đủ với NaOH ở điều kiện thích hợp thu được hỗn hợp sản phẩm . Đốt cháy hoàn toàn thu được 23,85g chất rắn (Z) nguyên chất cùng hỗn hợp khí và hơi (T). Hấp thụ toàn bộ (T) vào dung dịch chứa...

Cho x, y, z là ba số thực dương, thỏa mãn: 1/x + 1/y + 1/z = 3 Tìm giá trị nhỏ nhất của biểu thức P = [√ (2x^2 + y^2)]/xy + [√ (2y^2 + z^2)]/yz + [√ (2z^2 + x^2)]/xz

Write a new sentence as similar as possible in meaning to the original sentence, using the word given. You must use between three and eight words, including the word given. Do not change the word given. 1. I sincerely promise you that I’m telling you the truth. (bottom) → I promise you...

Finish each of the following sentences in such a way that it means the same as the sentence printed before it. 1. Tom hasn’t watched a football match for 2 months. → The last____________________________________________________ 2. “You should apply for that job. It is suitable for you.” Kevin...

Write the correct FORM of each bracketed word. 1. They entered the areas without (PERMIT)___________. 2. The giant panda is a(n) (DANGER)___________ species. 3. What makes the computer a (MIRACLE)___________ device? 4. You may be surprised at the large (VARIED)___________ of animals in...

Rewrite each of these sentences in such way that it means the same as the sentence printed before it. 1. Jenny entered the room quietly so that she would not disturb the lecturer.  So as …………………………………………………………………………………………. 2. The price of crude oil has decreased sharply in recent years. ...

Complete the second sentence 1. I met her while I was staying in Paris last summer. stay  I met her................................................in Paris last summer. 2. I couldn't remember the name of my hotel when I got into the taxi. called  I couldn't...

Write a new sentence similar in meaning to the given one, using the word given in the brackets. Do not alter the word in any way. 1. It was six months since I stopped subscribing to that magazine. SUBSCRIPTION  I cancelled ………………………………………………………six months ago. 2. These books are on loan...

Rewrite the following sentences in such a way that the second sentence has the same meaning as the first one. 1. Just thinking about his face at the moment makes me laugh.  The very ……………………………………………………………………………………… 2. We don’t have to do so many things to please him.  It is...

Give the correct form of the words in brackets 1. Please (know) .................................. our letter of the 25th. We have not had a reply. 2. Eating fish and lots of vegetables greatly increases your life (expect) ............................. 3. It is very rude to interrupt someone...

Fill in each blank with one suitable preposition or particle . 1. Dishonesty is foreign ……………. his nature. 2.Yuri Gagarin lifted …………… into space aboard the Vostok 1 at 9.07 a.m. Moscow time …………… 12th April, 1961. 3. She was free to indulge …………… leisure activity like reading. 4. Is it OK if I...

Một hỗn hợp gồm BaO, MgCO3, Al2O3 và CuO. Trình bày phương pháp tách riêng từng chất từ hỗn hợp trên với điều kiện không làm thay đổi khối lượng mỗi chất so với ban đầu.

You are going to read an extract from an article about a National Trust Warden. Choose from the list A-G the most suitable heading for each part (1-5) of the extract. There is one extra heading which you do not need to use. There is an example at the beginning (0). LOOKING AFTER THE COUNTRYSIDE...

Rewrite the following sentences so that they have the same meaning as the original one. 1. I left without saying goodbye as I didn’t want to disturb the meeting.  Rather ………………………………………………………………………. 2. That’s the last time I go to that restaurant.  I certainly …………………………………………………………………….. 3...

Choose the best answer A, B, C or D to complete the passage. It was a Monday morning in the office and , as usual , everyone was busy sorting through their mail before starting work . The other staff had (1) .........that Nicky , one of the computer operators , has been (2) ........... rather...

Supply the correct tens/from of the verbs. The clock (1. strike)……….……four as she (2. reach)………….….her flat. She (3. light)…………….a final cigarette and (4. sit)………………at her dressing-table (5. think)………….….of the party she (6. leave)…………..an hour before. She would have been home much earlier but...

Choose the best option A, B, C or D. 1. The scientists worked very hard and they finally achieved some marvelous results with this new drug. The synonym of "marvelous" is ______. A. disappointed B. compulsory C. wonderful D. convenient 2. The relationship is...