tại sao trẻ sinh đôi cùng trứng đều là nam hoặc đều là nữ

Cho tam giác ABC .Trên AB lấy D,trên AC lấy E sao cho BD=CE.Gọi M,N,P,Q lần lượt là trung điểm BC,CD,DE,EB. a,Chứng minh tứ giác MNPQ là hình thoi. b,Phân giác góc A cắt BC ở F .Cm PM song song với AF.c,Đường thẳng QN cắt AB và AC lần lượt ở I và K.Cm:Tam giác AIK cân.(câu a mik lm r)

Complete the sentences with the correct form(to-infinotive or -ing form) of the verbs in the box. Some verbs can be followed be iether a to- infinitive or an -ing form

ko cần GT chỉ cần đúng 5P làphải có bải xác định ngữ pháp và chỉ ra kiểu câu : bảo đổ bộ vào đất liền khiến nhiều nhà dân bị thiệt hại nặng nề

trộn 100ml dd HCL 0.5M với 100ml dd hcl 0.8M . Tính nồng độ mol của dung dịch sau trộn

Chỗ ghi là số cây mng chuyển giúp e là giấy vụn nhé cô giáo e in đề bị nhầm ạ Rồi vẫn giải như bth nhé

hòa tan hết 9,2 g kim loại natri và 15,5 gam natri oxit vào 800 g dd natri hiđroxit có nồng độ 5% tinh nồng độ phần trăm chất tan trong dd thu đc

10 Read the following passage, then choose the correct answer to questions: Yesterday, on the way home from school, I saw an accident. A boy was run over by a taxi when he was riding his bicycle. The boy"s leg was broken and it was bleeding badly. Someone there tried to stop the bleeding. They put pressure on it and held it tight. A man used his mobile phone to call the emergency service. Some minutes later, an ambulance arrived and sent the boy to the hospital. Two policemen came to the scene immediately. Some people told the police that the taxi driver was driving at a very high speed when the accident happened. Some others began talking about the traffic accidents these days and blamed the increasing number of accidents on the roads for careless driving and drunk drivers. Why does the number of accidents begin to increase these days? A. Because people don’t watch when crossing the roads. B. Because of careless driving and drunk drivers. C. Because careless driving and drunk drivers. D. Because drivers don’t stop when the lights turn green 11 Mark the letter A, B, C, D on your answer sheet to indicate a meaningful sentence from the words and phrases given parents / I went / Thailand / take part / the Songkran Festival / last April. A. My parents and I go to Thailand to take part in the Songkran Festival last April. B. My parents and I went to Thailand and take part in the Songkran Festival last April. C. My parents and I went to Thailand to take part with the Songkran Festival last April. D. My parents and I went to Thailand to take part in the Songkran Festival last April. 12 Mark the letter A, B, C, D on your answer sheet to indicate a meaningful sentence from the words and phrases given Save / energy / one / best / way / conserve / natural / resources // A. Saving energy is one of the best ways to conserve natural resources. B. Save energy is one of the best ways conserve natural resources. C. Saving energy is one of the best ways conserve natural resources. D. Save energy is one of the best ways to conserve natural resources. 13 Choose the sentence which has the same meaning with the given one. Despite the fact that it was snowing, I didn’t feel cold. A. Although I didn’t feel cold, it was snowing B. In spite of the snow, I felt quite cold. C. In spite of feeling warm, it was snowing. D. Although it was snowing, I didn’t feel cold. 14 Read the following passage, then choose the correct answer to questions: Yesterday, on the way home from school, I saw an accident. A boy was run over by a taxi when he was riding his bicycle. The boy"s leg was broken and it was bleeding badly. Someone there tried to stop the bleeding. They put pressure on it and held it tight. A man used his mobile phone to call the emergency service. Some minutes later, an ambulance arrived and sent the boy to the hospital. Two policemen came to the scene immediately. Some people told the police that the taxi driver was driving at a very high speed when the accident happened. Some others began talking about the traffic accidents these days and blamed the increasing number of accidents on the roads for careless driving and drunk drivers. What part of his body was hurt? - His _________. A. shoulder B. head C. leg D. arm 15 Mark the letter A, B, C, D on your answer sheet to indicate a meaningful sentence from the words and phrases given people / love / festivals / because / advantages / they / bring about. A. People love festivals because with the advantages they bring about. B. People love festivals because the advantages they bring about. C. People love festivals because of there are advantages they bring about. D. People love festivals because of the advantages they bring about.

mn giúp em với ạ em đang cần gấp ạ

làm nhanh giúp mình nhé 12h trưa nay mình phải nộp r