Cho 20 gam hỗn hợp gồm Fe và ZnO tác dụng vừa đủ với dd HCl thì thu được 2,24 lít khí hidro (ở đktc). Thành phần phần trăm khối lượng của ZnO trong hỗn hợp ban đầu -Trình bày chi tiết hộ ạ!cảm ơn

Mọi người giúp mình với ạ :(( Toán lớp 6 đó

1. Mr Jones gave the people gloves and said to them: "Protect yourselves from germs." Mr Jones ______________________________________________________________. 2. Nam said, "The environment is severely affected by pollution." Nam said ______________________________________________________________. 3. Mai said, "The burning of fossil fuels leads to air pollution." Mai said ______________________________________________________________. 4. Peter said, "Intensive insecticide and pesticide sprays in agriculture make the soil contaminated." Peter ______________________________________________________________. 5. "It's confusing because there are too many web pages about the environment" Nam said. Nam said ______________________________________________________________. 6. "Air pollution is one of the causes of the greenhouse effect" scientists said. Scientists said ______________________________________________________________.7. "Pollution is one of the problems in my neighbourhood" Nam said. Nam said that ______________________________________________________________. 8. "More people are aware of the preservation of natural resources" the editor said. The editor said ______________________________________________________________. 9. "We are discussing the protection of the natural environment" the students told their teacher. The students told ______________________________________________________________. 10. "Use the web search engine to find the information that you need" Nam's father told him. Nam’s father told ______________________________________________________________.

sắp xếp rồi tính: (-10x^2 + x^4 - 9 ) : ) : (x^2 -2x - 3)

1) (x-1)(x+3)=x^2+4 2) (x-2)^2=(x-3)(x+2) 3) (x-1)(x+3)-(x+2)(x-3)=0 4) (x-2)(x-5)-(x-3)(x-4)=0 5) (3x-2)(4x+3)=2x(6x-1) ----mong mọi người giúp mình vs----

Cho hình thang cân ABCD, có đáy lớn CD, đáy nhở AB. Qua A kẻ đường thẳng // với BC, cắt BD ở E. qua B kẻ đường thẳng // với AD, cắt AC ở F a, Chứng minh tứ giác DEFC là hình thang. b, Tính độ dài đoạn EF nếu biết AB=5cm, CD=10cm. Giúp mình nhé!! :)

Gieo 4 đồng xu cân đối đồng chất.Tính xác suất để được 4 mặt giống nhau

11. “Are you good at chess?” - “ I’m the ______chess player in the world.” A. bad B. worse C. worst D. baddest 12. We need ________ to sleep in when we camp overnight. A. a bed B. a sleeping bag C. a backpack D. a torch 13. “___________!” - “ Thank you. My mother gave me on my last birthday.” A. What nice shirt B. How beautifully the shirt is C. How pretty you are in this shirt D. What nice shirts you have 14. If we cycle more, there_______ less air pollution. A. will be B. are C. have been D. was 15. There aren’t ________good books at this bookstore. A. much B. some C. a lot D. any 16, Don’t touch that dog. It …….. bite you. A. will B. was going to C. is going to D. be going to 17, ……… kind of books do you like? A. Which B. What C. Whose D. Whom 18, Would you like to stay at home …….. go out? A. or B. but playing C. and D. if 19, I was driving along East Street when I ……….. a fire. A. saw B. see C. had seen D. was seeing 20, Do you enjoy ……….. to classical music? A. listen B. to listen C. listened D. listening 21, My father is very interested ………. gardening. A. on B. in C. for D. at 22, English is learned by millions of students ………. its importance. A. because of B. because C. despite D. although

thanh thủy tinh tích điện dương khi cọ xát vào lụa, mảnh polieetilen tích điện âm khi cọ xát vào len. Đưa mảnh lụa và mảnh len lại gần nhau thì: a/ ko hút, ko đẩy nhau b/ hút lẫn nhau c/ vừa hút vừa đẩy nhau d/ đẩy nhau

Giúp mình mấy câu hỏi bị động với