Hỗn hợp khí gồm NO,N2O và N2Ox có tỉ khối đối với khí hidro là 23,1.Trong hỗn hợp trên có số mol N2Ox bằng 2/3 số mol của NO,mặt khác N2O chiếm 47,62% về khối lượng hỗn hợp .Xác định CTHH của N2Ox và thành phần % về thể tích của mỗi khí trong hỗn hợp.

Tính: A = $1^{2}$ + $3^{2}$ + $5^{2}$ + ... + $(2n-1)^{2}$

a) Góc tạo bởi đường thẳng y= x+5 và trục Ox là? b) góc tạo bởi đường thẳng y=-x+5 và trục Ox LÀ?

tổng số đo của hai góc vuông là A:số đo của một góc bẹt B: số đo khác 180 độ C:tổng số đo hai góc phụ nhau D: một số đo lớn hơn 180 độ

Bài 3: Khoanh tròn vào liên từ thích hợp để hoàn thành những câu phức dưới đây. 1. It will be a great fortune (if/unless) I can join upcoming carnival. 2. I will lend you my book (as long as/as soon as) you promise to keep it clean. 3. I will call you (as long as/as soon as) I arrive there. 4. (When/While) I came, Jim was having dinner. 5. Catherine was shocked (when/until) she found out the truth. 6. They have worked at this company (when/since) they graduated. 7. At 8 pm last night, I was doing my homework (when/while) my sister was playing with her toys. 8. (Before/After) I had eaten my breakfast, I went to school by bus. 9. (Although/Despite) Mary looks thinner than me, she is much stronger than me. 10. They didn’t come to the party (since/as soon as) they were too busy. 11. You should bring your raincoat (unless/in case) it rains. 12.I didn’t realize her new hair (when/until) she told me. 13.I won’t accept this job (even if/if) the offer me high salary. 14.My father will buy me a book (even though/as long as) I pass the exam. 15.I like her (when/even though) she’s annoying sometimes. Bài 4: Điền những liên từ cho sẵn vào chỗ trống để hoàn thành những câu phức dưới đây. whereas unless x2 since before x2 if x2 even though while 1...................... Jame is my friend, I can’t accept his arrogance. 2. My brother is a bookworm, ................... I don’t like reading books. 3. At midnight, my parents were sleeping..................... I was cramming for exams. 4................... you have any questions, you ask me after the lesson. 5. We won’t go camping.................. the weather is fine. 6. You shouldn’t skip classes...................... you really have to. 7. What did you do.................... you went to bed last night? 8. In some cultures, you have to pray........................ you eat. 9. We are very familiar with this areas................... we moved here 15 years ago. 10.................... you travel from the North to the South of Vietnam, you will experience many interesting customs. Bài 5: Viết lại hai câu đơn thành một câu phức. 1. Dog is my favorite animal. They are good companions of people. ..................................................................................................................... 2. I don’t like jazz . A friend of mine is a fan of it. ..................................................................................................................... 3. They were stuck in the traffic for hours. They managed to get there on time. ..................................................................................................................... 4. I came to the party. Everyone was leaving. ..................................................................................................................... 5. This time Jane works very hard . She doesn’t want to fail the exam again. ..................................................................................................................... 6. I seldom do exercises. I doing exercises is good for health. ..................................................................................................................... 7. My computer is old-fashioned. It functions very smoothly. ..................................................................................................................... 8. I didn’t know her real name. People always called her by her nickname. ..................................................................................................................... IV. Fill in each blank with one suitable subordinate from the box. . VI. State whether the following sentences are simple, complex or compound. 1. The Elephant Racing Festival is the biggest cultural festival in Tay Nguyen. 2. You can either choose to ride in a cable car up to the pagoda or walk up. 3. We first learned to sing quan ho when we were between 15 and 17. 4. The oarsmen are encouraged by the sounds of drums and the cheering crowds while they are racing. 5. Maya doesn’t follow the procession, but she supports the dancing team. 6. Hundreds of thousands of people gather on the two banks of the river to watch the Ngo junk race. 7. Ngo junk race is a community sports which enhance unity among Khmer people from villages. 8. Even though many people come to Buon Don to ride the elephants, a lot of them fail to witness the Elephant Racing Festival. 9. Tet is the most important festival in Vietnam; therefore, most Vietnamese return home for Tet. 10. They played together as a team very well; however, they didn’t win the race. 11. After taking a boat to the mountain, we can take a cable car up. 12. It was an exciting festival, so I felt very lucky to participate in it. 13. Last year, I went to Huong Pagoda with my family and friends.

Giải hộ mk bài này cái rồi mk sẽ đền bù xứng đáng nha !!!!

I didn't eat dinner with everyone, so I feel very hungry now chuyen thanh cau theo cau truc cau dieu kien

Mọi người thiết kế cho mình một vài cái nhãn vở nha

6. She didn't make the moon cakes last week. 7. He doesn't meet them in her school everyday. 8. Anna won't wtite a letter. 9. The workers haven't decorated their building yet. 10. The police hasn't arrested a burglar. 11. Two people aren't cooking dinner on the beach. 12. Tina isn't doing grammar exercises. 13. At this time last year, they ­­­­­­­­­­­­weren't building this house. 14. I wasn't chatting with my friends while my teacher was teaching the lesson yesterday. 15. After the children hadn't finished their homework, they went to bed. 16. When she hadn't done her work she went to the cinema. 17. I am not going to watch films with my friend because I am sick. 18. My sister isn't going to cook a delicious meal for dinner.

Cho 5,6g Fe tác dụng với dd AgNo3 dư.Giả sử phản ứng xảy ra hoàn toàn thì khi sắt tác dụng hết sẽ thu được bao nhiêu gam bạc. Mong các chuyên gia và các bạn học sinh giỏi giải giúp với ạ! Cảm ơn nhiều!