Một hợp chất khí X đc tạo bởi Lưu huỳnh và Oxi có côg thức SxOy , biết trog phân tử X có 3 nguyên tử và tỷ khối của X đối với không khí là2. Xác định côg thức phân tử X

Dựa vào bài đã học từ bài 17 đến bài 20 lớp 10 em hãy rút ra các thành tựu tiêu biểu và nhận xét tình hình nước ta trong thời kì dựng nước

X^2Y^2 +(X-2)^2+(2Y-2)^2 -2XY(X-2Y+4)=5 HAY TIM CAC NGUYEN NGUYEN X Y THOA MAN

Cho x+y-13+z-10=2020 biết x+z-y=30

Giúp e vs ạ thanks I. Read the passage. Then choose one suitable word to fill in the gaps. (1.0 point) Mr. Thanh is (1)________ engineer in a big factory. He lives in a small apartment (2) ________ the fifth floor of a building in Ho Chi Minh City. The factory is not near (3) ________ so he goes to work by bus. He (4) ________ home at 7 o’clock to arrive to work at 7.45. (5) ________ is Saturday morning now, and Mr. Thanh is (6)________ home, in bed. On Saturdays he (7)_______ at a quarter to seven. Then he sits in the living room and (8)_______ breakfast. On Saturday afternoons he (9)_______ tennis or goes swimming. On Saturday evenings he (10)_______ at home, he usually goes out. 1. A. a B. an C. the D. any 2. A. at B. in C. on D. of 3. A. house B. he’s house C. him house D. his house 4. A. leaves B. is leave C. leaving D. leave 5. A . It B. It’s C. Their D. They 6. A. in B. at C. on D. with 7. A. get up B. to get up C. getting up D. gets up 8. A. have B. having C. has D. to have 9. A. plays B. is play C. play D. is playing 10. A. not stay B. doesn’t stay C. isn’t stay D. no staying

1. Tìm x Î Z biết: a) x(x+3) = 0 b) (x – 2)(5 – x) = 0 c) (x-1)(x2 + 1) = 0

Cho tam giác ABC cân tại A . Trên cạnh BC lấy các điểm D,E sao cho BD = EC<1/2BC a, Chứng minh tâm giác ADE là tâm giác cân b, kẻ DH vuông góc với AB tại H , EK vuông góc AC tại K . Chứng minh rằng BH=CK c, gọi I là giao điểm của DH và EK . CHứng minh rằng tam giác IDE cân tại I d, Chứng minh AI là tia phân giác của góc BAC Giúp mik với mik vote 5 sao luôn ạ

Trên thế giới có bao nhiu mét khối không khí🤣🤣🤣❤

Anh chị giúp e giải bài 6 vs ạ . Em cảm ơn ạ.

Exercise 10: Choose the best answer for each of the following sentences. 1. ………………… have enough apples, she’ll make an apple pie this afternoon. A. Should she B. If she C. Will she D. Unless she 2. If you ………………… to me, you wouldn’t have got so much trouble. A. listened B. would listen C. had listened D. would have listened 3. If you don’t know how to spell a word, you ………………… look it up in the dictionary. A. must B. will C. should D. ought 4. If the sun …………………, we ………………… for a walk. A. shines - will go B. shone - will go C. shone - would go D. had shone - would go 5. The campfire ………………… if it ………………… last night. A. wouldn’t be cancelled - hadn’t rained B. wouldn’t have been cancelled - hadn’t rained C. would have been cancelled - hadn’t rained D. will be cancelled - rains 6. But for our parents, we ………………… successful in life. A. will never be B. would never be C. wouldn’t have been D. would have never been 7. If I ………………… my wallet at home this morning, l ………………… money for lunch now. A. leave - will have B. didn’t leave - would have C. hadn’t left - would have D. hadn’t left - would have had 8. It is too bad, Lam isn’t here. If he ………………… here, he ………………… what to do. A. were/ would know B. is/ will know C. had been/ would have known D. was/ would know 9. If we ………………… the plans carefully, we would not have had so many serious mistakes. A. study B. had studied C. studied D. were studying 10. I ………………… will never talk to you again ………………… you apologize me ………………… your being rude. A. if - for B. unless - for C. or - of D. whether - or 11. ………………… you work harder, you will be sacked. A. Whether B. If C. However D. Unless 12. I think you should stop smoking. A. If I am you, I will stop smoking. B. If I were you, I will stop smoking. C. If I were you, I would stop smoking. D. If I had been you, I would stop smoking. 13. If you take the ice out of the fridge, it ………………… A. vaporizes B. melts C. heats D. disappears 14. We should do something to protect water from being polluted ………………… we will have nothing to drink in the future. A. if B. whether C. or D. unless 15. Let’s knock on their door to see ………………… home. A. if they’re B. unless they’re C. whether they were D. if they were 16. Unless we ………………… more snow, we can’t go skiing. A. will have B. have C. have had D. had 17. You’ll fail the exam ………………… you start revising. A. if B. until C. when D. unless 18. Unless you wash the car, you ………………… not drive it at the weekend. A. would B. could C. have to D. may 19. If Peter ………………… his car before the drive, he ………………… the problem of out of petrol. A. checked - will not get B. had checked - would not have got C. checks - will not have got D. would be checking - will not have got 20. He stepped on the mine, and it exploded. A. If he doesn’t step on the mine, it doesn’t explode. B. If he doesn’t step on the mine, it won’t explode. C. If he didn’t step on the mine, it wouldn’t explode. D. If he hadn’t stepped on the mine, it wouldn’t have exploded. 5 sao + 1 câu trả lời hay nhất + 1 cảm ơn