giải phương trình: cos⁡x.cos⁡2x.cos⁡4x+1/(8 sin⁡x )=0 giúp mình với :((((

Ca(OH)2 + H2SO4 ---> CaSO4 + H2O

Giúp e với ạ, giải ra kĩ càng tốt ạ:(( Chỉ 3-4 câu thôi cũng được ạ, không cần full đâu :((

Cho A1+B1=180 độ so sánh So le trong, đồng vị

Phân tích đa thức thành nhân tử : 8a³+4a²b-2ab²-b³

. Nguyên tố X có 3đồng vị. X1 chiếm 92,23% số nguyên tử, X2 chiếm 4,67%. Tổng số khối của 3 đồng vị là 87. Số nơtron của X2 nhiều hơn X1 là 1 hạt. Nguyên tử khối trung bình của X là 28,0855. Tìm số khối mỗi đồng vị.

giải hộ mình 2 câu này mình cần gấp giải giúp mình nha cam on mng!

Trả lời đầu tiên là trả lời hay nhất :))) Complete the correct answer a, b, c or d. Question 11. How much time do you spend _______ TV every day? A. watch B. to watch C. watching D. in watching Question 12. I’d hate _______ the exams, so I’m doing my best. A. failing B. to failing C. fail D. failed Question 13. I always enjoy _______ to my grandfather. He always tells me great stories. A. to talk B. to talking C. talking D. talk Question 14. Could you help me _______ the kitchen? It’s a real mess! A. tidy B. tidied C. tidying D. with tidying Question 15. Steven dislikes _______, so he usually takes a bus to work. A. drove B. to be driven C. be driven D. driving Question 16. Jane prefers _______ music than to listen to it. A. playing B. to playing C. to play D. played Question 17. Marlene can’t wait _______ to the beach again. A. to go B. going C. for going D. go Question 18. I really regret _______ this computer – it’s useless. A. buy B. to buy C. buying D. for buying Question 19. Your child needs _______ some weight. Tell him _______ less junk food and more exercise. A. to lose - eat B. to lose - to eat C. losing - to eat D. losing - eat

Vẽ đậu mầm/chibi OR calli: Im fine Nl:có thg 2k3 đòi cưới toy:))

11. I rarely eat ____ and drink ____ because they're not good for health.   A. snack/energy drink     B. fast food/juice     C. fruit/alcoholic drink D. junk food/soft drink   12. Generation ____ is the difference in the thoughts and viewpoints amongst generations living together.   A. distance   B. gap   C. space.   D. All are correct   13. I was tired and couldn't ____ on doing my research project properly.   A. concentrate B. look   C. pay attention D. Both A and C   14. My parents don't let me get married until I graduate from university and they never ____ their mind about that.   A. keep   B. impose   C. focus  D. change   15. The ____ arises when Jack and his parents have considerable disagreement on his choice of university.   A. discrimination B. conflict   C. agreement  D. gap   16. I do morning exercise and play volleyball regularly so as to keep ____ and be healthier.   A. fit    B. good shape   C. healthy  D. strong   17. My father used to ____ a lot of challenges before establishing his own insurance company.   A. provide   B. enjoy  C. give   D. face   18. I wish I could do something to reduce financial ____ on my parents.   A. capital   B. burden  C. limit   D.  gap