(-85)+10-(-85)-50 >>>>>>>>>>>>>>>>>

Đường kính của một bánh xe đạp là 0,52. a, Tính chu vi bánh xe đó là bao nhiu? b,Chiếc xe đó sẽ đi được bao nhiêu m nếu bánh xe lăn trên mặt đất 50 vòng, 80 vòng, 300 vòng?

Vì sao bước sang thu đông 1950, Đảng và Chính phủ ta lại quyết định mở chiến dịch biên giới?

Tại sao không nên nhìn quá gần quá lâu khi đọc sách xem ti vi điện thoại và khi làm việc với máy tính

Một hình chữ Nhật có chu vi là 172 phần 3 cm , chiều dài hơn chiều rộng 18 phần 3 cm .hỏi diện tích hình chữ Nhật là bao nhiêu? ( kết quả dưới dạng phân số tối giản) Bài 2: một hình chữ Nhật có chiều dài 1phần 5 m , chiều rộng là 1phần 20 m .chu vi hình chữ Nhật là bao nhiêu? Bài 3: cho hình bình hành abcd có am =16cm, an =28cm,diện tích hình bình hành abcd là 1344cm vuông.tính chu vi hình bình hành

Tính S1 = 1 + 2 + 22 + 23 + … + 263

1. It last rained here two months ago. A. It hasn’t rained here for two months B. There was no rain here two months ago C. It has rained here for two months D. It hasn't rained here for two months 2. She doesn’t speak Spanish so she cannot work for them. A. If she speaks Spanish, she can work for them B. If she spoke Spanish, she could work for them C. As she doesn't speak Spanish, she can work for them D. She can work for them if she spoke Spanish 3. He will die if nobody brings him to hospital at once. A. He will die unless he is brougt to hospital at once B. He will be saved if he isn't brought to hospital at once C. Since nobody brings him to hospital at once, he will die D. He is brought to hospital at once, so he won't die 4. "Please wake me up at 6 tomorrow morning", I said to my mother. A. I said to my mother to wake me up at 6 the next morning B. I told my mother that I would wake up at 6 the next morning C. I promised my mother to wake up at 6 the next morning D. I asked my mother to wake me up at 6 the next morning 5. The garage is going to repair the car for us next week. A. We are repairing the car in the garage next week B. The car is being repaired by the garage next week C. We are having the car repaired by the garage next week D. We are having the garage to repair the car next week 6. Mr. Pike used to live in this town. We bought his land. A. Mr. Pike, we bought his land, used to live in this town B. Mr. Pike, whose land we bought, used to live in this town C. Mr. Pike, his land we bought, doesn't live in this town D. Mr. Pike from whom we bought land doesn't live in this town 7. The test was very difficult. We couldn't finish it A. It was such a difficult test that we couldn't finish it B. The test was too difficult that we couldn't finish it C. We couldn't finish the test; therefore, it was so difficult D. We couldn't finish the test; as a result, it was so difficult 8. The volunteers won't come back to this area soon. A. If only the volunteers came back to this area soon B. We hope the volunteers wouldn't come back to this area soon D. We wish the volunteers will come back to this area soon D. We wish the volunteers would come back to this area soon

Hiiiiiiiii Giúp mềnh vs nhé !!!!

Nêu chức năng của đại não( chức năng của từng vùng) Mong mng giúp em ạ

`1 + 78/9 + x = 1` .................