Cho tam giác ABC cân tại A gọi M,O lần lượt là trung điển BC và AB gọi N là điểm đôi xứng M qua 0 a) tính diện tích tam giác ABC,biết AC=5cm BC=6cm b) tứ giác AMBN là hình gì? Vì sao? c) tâm giác ABC có thêm điều kiện gì thì tứ giác AMBN là hình vuông?

Cho tam giác ABC. điểm M thuộc đoạn thẳng BC sao cho BM=2CM. Trên tia đối của tia CA lấy điểm D sao cho CD=CA. Gọi E là giao điểm của AM và BD. a) Chứng minh M là trọng tâm tam giác ABD. b) Chứng minh AM đi qua trung điểm của BD. GIÚP MK VỚI Ạ! MK ĐG CẦN GẤP

Người tối cổ nước ta sinh sống ở đâu?

cho em hỏi từ dòng 4 xuống dòng 5 kiểu gì ạ em không hiểu

IX. Choose the word or phrase among A B, C or D that best fits the blank space in the following passage. Have a walk (1) a beach, listen to the sound of the sea waves, and suddenly you see a lot of rubbish on the beach. Pollution takes away all the (2) of out beaches. I feel reallyvery annoyed (3) I see plastic lying on the sand, cigarette ends buried in the sand, and soda cans floating in the sea. There are a lot of things that we can do. (4) we see rubbish, we should do our part in the protecting the land (5) picking it up and throwing it in dust bins. (6) , we can form some kind of organization that helps (7) the beaches. If everyone does their part, the beach will be a wonderful and beautiful place. We need to start now (8) the beaches are damaged beyond repair. 1. A. at B.in C.on D.over 2. A. beauty B.beautiful C.beautifully D.being beautiful 3. A.before B.after C.When D.While 4. A.While B.If C.Unless D.Soon 5. A.by B.with C.of D.in 6. A.Nevertheless B.Therefore C.However D.Moreover 7. A.cleaning up B.clean up C.cleaning up D.clean off 8. A.before B.after C.until D.when X. Read the passage, and choose the correct answer A, B, C or D for each question. Saving the Environment: One Home at a Time Pollution can be seen not only throughout the world, but also in our own homes. It comes from household chemicals, the amount of water people use and the waste people produce and throw away. What can be done to stop this pollution? Surprisingly, a person can help save the environment by doing simple things. First, we need to recycle, which allows products to be used over and over again. Recycling can also reduce the number of trees cut down to produce paper products. It takes very little effort. It is not hard to place plastic and glass bottles, aluminum cans and paper in a bin. Anyone can do it. Second, we need to watch the amount of water used in the home. It can be conserved by taking short showers instead of baths, repairing leaky faucets, using the dishwasher or washing machine only when fully loaded, or simply turning the faucet off while brushing your teeth. Third, we need to reduce waste. We need to recycle whenever possible, but should also try to use this waste effectively. For example, grass clippings and food scraps can be made into compost for plants. The average person produces 4.3 pounds of waste every day, but we can reduce that amount by recycling and reusing. If we do our part in our own homes, we can help keep the planet from becoming more polluted. 1. Pollution can be caused from the following sources except . A. house chemicals B. water from households C. wastes D. water in rivers 2. Recycling can help us . A. never cut down trees B. use products again and again. C. place garbage bins easily D. produce more paper products 3. In order to save water, we can do all of the following things except . A. take short showers instead of baths B. repair leaky faucets C. fully use the washing machine D. turn the faucet off while brushing your teeth 4. Recycling helps to reduce waste because . A. plants need to develop B. a person can do it in his home C. waste can be recycled and reused D. an average man produces compost for plants 5. The word "It" in paragraph 2 refers to . A. recycling B. the number C. cutting down D. effort XI. Write a paragraph about noise pollution (definition, causes, effects and solutions), using the cues given. 1. Noise pollution/ any loud sounds/ either harmful or annoying/ humans and animals. 2. Generally/ noise/ produced/ household appliances/ big trucks/ vehicles and motorbikes/ on the road/ planes and helicopters flying over cities/ loud speakers, etc. 3. Noise solution/ cause/ stress/ illnesses/ hearing loss/ sleep loss/ lost productivity. 4. Health effects/ noise/include/ anxiety/ stress/ headaches/ irritability/ nervousness. 5. Noise-producing industries/ airports/ bus terminals/ should/ located/ far/ living places. 6. The officials/ check/ misuse/ loudspeakers/ outdoor parties and discos/ as well as/ public announcement systems. XII. Rewrite the sentences, using the words in brackets. You can make some changes. 1. There are asthma, allergies and other respiratory illnesses when air pollution happens.(leads to) 2. Aquatic life suffers or dies because there is thermal pollution.(because of) 3. Water in the Cau River becomes brown and has terrible smell because the waste water is released from the paper mill in Thai Nguyen City.(so) 4. People use much herbicide to treat weeds, so waterin rivers, canals, lakes are extremely polluted and has bad effects on people’ health. (because) 5. May fish in the river die due the increased temperature of water.(because) 6. Because plastic bags take so long to decompose, nearly all of them still exist in the environment today. (so

my parents are born in Vietnam Lại sao câu này lại dùng động từ tobe are mà ko phải là were ạ

Mọi người giải giúp em vớiiii ạ!!

what........she (do) .......? She (be)......a teacher

các bạn làm giúp mik bài này vs ạ nhiều bài tập quá làm ko nổi hiccc:))

cho 1g sắt clorua chưa rõ hóa trị của fe vào dd AgNo3 dư, ng ta thu đc 2.65 g 1 chất kết tủa trắng. xác định công thức của muối sắt clorua . Mng giúp mk với ạ