Âm thanh tiếng chim tu hú kêu có ý nghĩa rất đh trong bt KHI CON TU HÚ.Hãy chỉ ra

a) ở mặt đất một người có trọng lượng 600N thì ở mặt trăng người đó có trọng lượng là bao nhiêu?

hai so co tong bang 700. tim hai so do biet rang so thu 1 gap 4 lan so thu 2

Ai lam ho em 4 5 6 voi em hua se tang 5 sao a

I. Give the correct form of the verbs in brackets. 1. We (be) ____________ happy if air pollution were the only problem. 2. They would be disappointed if you (not go) _____________ to their party. 3. If we (use) _______ this kind of light bulb, we can save energy. 4. Peter should go to sleep early if he (not want) ____________ to be tired the next morning. 5. If you (take) _______________ more exercises, you would be more resistant to diseases. 6. You may have car accident unless you (drive) ________________ more carefully. 7. If I travel to London, I (visit) ____________ its museum. 8. If they offer me the job, I think I (accept) _________________ it. 9. Many people (be) ____________ out of work if the local factory closed down. 10. What (happen) _________________ if that red button was pressed? 11. I’d be absolutely astonished if Mary and James (get) _____________ married. 12. They won’t let you in unless you (show) _____________them your identity card. 13. My best friend gave me this book. She (be) ________________ very upset if I lost it. 14. Would you mind if I (turn) ________________ up the radio. 15. I’m sure she (forgive) ______________ you if you sincerely apologize to her. II. Put v if the sentence is correct and x if it is incorrect then write the correct sentences. 1. Pollution can be reduced if we joined hands to prevent it. 2. If farmers would make use of pesticide more wisely, the soil would not be poisoned. 3. I won’t believe it unless you showed me the evidence. 4. Unless you don’t tell me the truth, I won’t help you. 5. If James is more outgoing, he would have more friends. 6. I think the show would be successful if he were one of the organizers. 7. If you paid more attention to what I said, you didn’t make so many mistakes. 8. If children are taught about environmental issues, they might change their attitudes towards pollution. 9. You would be punished if you park your car here. 10. If you could win the competition, we will have a celebration. III. Circle the correct answer to complete the passage. Consequences of water pollution Water pollution is a matter of concern nowadays because of its negative effects on the environment and human. The first problem is that water pollution kills (1) ________ organism. Dead fish, crabs, birds and sea gulls, dolphins, and many other animals have been killed by (2) ____________ in their habitat. Moreover, pollution (3) _______ the natural food chain as well. Pollutants such as lead and cadmium are eaten by tiny animals. Later, these animals are consumed by fish and shellfish, and the food chain continues to be disrupted at all high levels. Eventually, humans are (4) ___________ by this process as well. People can get (5) ______ such as hepatitis by eating seafood that has been (6) ______________. In many poor nations, there is always outbreak of cholera and diseases as a (7) ______ of poor drinking water treatment from contaminated water. (8) ________ people don’t prevent pollution, not only the environment but also their health will be put at risk. 1. A. aquatic B. atmosphere C. underground D. soil 2. A. pollutes B. Pollution C. polluted D. pollutants 3. A. changes B. disrupts C. pollutes D. clears 4. A. affect B. affected C. affecting D. effect 5. A. illness B. sickness C. diseases D. healthiness 6. A. cleaned B. poisoned C. processes D. prepared 7. A. outcome B. effect C. way D. result 8. A. If B. Unless C. When D. In case

Một chiếc đĩa cân thăng bằng khi : ở đĩa cân bên phải có các quả cân 100g, 50g, 20g, 20g, 5g, 2g và 1g. Hãy xác định khối lượng của một gói bánh và một gói kẹo. Cho biết các gói bánh giống hệt nhau, các gói kẹo giống hệt nhau

bài 1 :tìm hai số nguyên x ,y 1) (x-3).(y+2)=7 2) (2x+1).(3y-2 ) =-55 3) xy-3y=-19 4) xy-4x+y=9

Cho $A=7^{6321}+5^{9876}$ a)CMR:$A$ chia hết cho $45$ b)Viết tập hợp $B⊃n$ để $A \vdots 3n$ c)So sánh $7^{6321}$ và $5^{9876}$

Câu 1:tính chu vì vườn trường hình chữ nhật dài 1hm,rộng 6 dam Câu2: tính chu vì một bàn hình vuông, có cạnh là 8dm. Câu 3: đàn gà có 72 con , 1 con là gà trống .Hỏi có bao nhiêu con gà mái.. Làm giùm mình nha ....cảm ơn

Câu 1: Thực hiện phép tính a) 17 + (– 51) + ( – 19) b) ( – 39).62 + 38.(– 39) c) (216 – 305) – ( 16– 305) d) ( – 8).25 .(– 125).9.(-4) e) ( – 9)^2 : 3^2 + |– 9| – (– 201) Câu 2: Thực hiện phép tính a) 35 – (– 51) + ( – 28) b) 122.(– 12345) + 12345.(– 78) c) (63 + 549) – ( 549– 37) d) ( – 4).(– 20).25.(-5).37 e) 2357^0– 2^4. 5+ |– 218| – (– 31) Câu 3: Thực hiện phép tính (hợp lí nếu có) a) 264 + ( - 295 ) b) 14 . ( - 6 ) + ( -4 ).( - 6 ) c) -15.-8+(-5)3--15 d) 23.32- -12 +-16 .6 Câu 4: Thực hiện phép tính (hợp lý nếu có thể) a) 235 + (-276) b) 216 . (-38) + (-62) . 216 c) (-125) . (-25) . 8 . (-4) . 62 d) 2016 0 – 32 .4 + |- 126| - (- 9) Câu 5: Thực hiện phép tính (hợp lí nếu có) a) 264 + ( - 295 ) b) 14 . ( - 6 ) + ( -4 ).( - 6 ) c) -15.-8+(-5)3--15 d) 23.32- -12 +-16 .6 Câu 6: Thực hiện phép tính (hợp lý nếu có thể) a) 235 + (-276) b) 216 . (-38) + (-62) . 216 c) (-125) . (-25) . 8 . (-4) . 62 d) 2016 0 – 32 .4 + |- 126| - (- 9) Câu 7: a) Tìm các số nguyên n sao cho 1 + n là ước của 13 b) Tính nhanh : A = 1 – 3 + 5 - 7 + 9 - 11 + … - 99 + 10 Câu 8: Tính nhanh : A = 2 + ( –5) + 8 + (– 11) +….+ 314 + (– 317) + 320 Câu 9: Tính nhanh : B = 12 + (– 15 ) + 18 + (– 21) + ….+ 324 + (– 327) + 330