Giup mik cau b va cau c vs mn oi Hua vote 5 sao+cam on va binh chon ctlhn Cho hình chữ nhật ABCD có AB>BC. Từ A vẽ AH vuông góc với BD ( H thuộc BD). a)Chứng minh: Tam giác ABD và tam giác HBA đồng dạng b)Chứng minh AH.BD= AD. CD. c)Phân giác của góc ABD cắt AH và AD lần lượt tại M và N . gọi K là hình chiếu của N trên DB. Chứng minh BH.MA=BK.MH.

So sánh sự cháy với sự oxi hóa chậm

Giúp teo cần rất gap cho 20 điểm đó nhanh nhé

7/5 nhân ( 4/21 ) rút gọn nếu có thể

GIải giùm mình vs ạ!Giải theo kiểu hàm số liên tục ạ

Giúp mình viết lại câu từ 23 đến 33 với

Phân tích 0,9 g A thu được 1,76 g CO2, 1,26 g nước, 224cm3 khí N ở đktc. Xác định công thức phân tử của A, bbieets tỉ khối của A đối với NO là 1,5.

20. The old man _________a black suit is a famous energy researcher. A. to wear B. wearing C. whom is wearing D.is wearing 21. Airplanes _________in the twentieth century is one of the sources of pollution. A. which invented B. to invent C. invented D. that is invented 22. We have an apartment_ ___________.the park A. overlooking B. overlooks C.to overlook D. overlooked 23. If energy _________ inexpensive and unlimited, many things in the world would be different. A. is B. will be C. would be D. were 24. Mohandas K. Gandhi, ______ Mahatma, lived a noble life of fasting and poverty in order to work for peace and independence. A. that was called B. was called C. called D. calling 25. Do you know the reason_______ she quit her job? A. that B. which C. when D. why 26. Alice: "What shall we do this evening?" – Carol: "______" A. No problem. B. Let’s go out for dinner. C. Oh, that’s good! D. I went out for dinner. Mark the letter A, B, C or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions. 27. Because power demand is increasing very rapidly, fossil fuels will be exhausted within a short time. A. enabled B. tired C. bushed D. used up Mark the letter A, B, C or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions. 28. Solar energy is not only plentiful and infinite but also clean and safe. A. unlimited B abundant C. limited D. rich Choose the word or phrase - a, b, c or d - that needs correcting. 29. In just (A) three months H.G. Wells wrote (B) the famous classic The Time Machine for what (C) he won a (D) Newberry Caldecott award. 30. Because much (A) species of plants and animals in Hawaii (B) ate threatened with (C) extinction within a short period of time, scientists are trying desperately (D) to rescue them. Choose the word or phrase among A, B, C or D which best fits each gap of the passage. We need energy to live and work. Our major source of…(31)……….is oil. Oil is one kind of fossil fuel. The amount of fossil fuel in the world is……(32)….Therefore, we must save it, and the same time, we must find new sources of energy. Geothermal heat and nuclear power are……(33)….sources of energy. They can give us electricity. Other alternative sources are the sun, waves and water. The sources are not only …(34)……and available but also clean and safe for the…(35)…People should develop and use them more and more in the future. 31. A. energy B. energetic C. energize D. energetically 32. A. limit B. limitation C. unlimited D. limited 33. A. alternative B. polluted C. harmful D. expensive

làm hộ e câu 6 em đang cần gấp

Cá muốn sống dc phải co khong khi ,nhung ta thay ca van song duoc duoi nuoc ,tai sao?