173/Một oxit nitơ có tỉ số khối lượng giữa 2 nguyên tố nito và oxi bằng 7:4. Xác định công thức hóa học

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THE WET SEASON IN INDONESIA. Between the months of November and May, a wind blows from the west in most parts of Indonesia. It comes from the ocean and carries rain. Clouds build up around the mountains, and every afternoon rain falls. The rain is always heavy, and river can be walked across in the dry season now become dangerous. When it rains the whole day, they may suddenly overflow and cause great damage to the land. Most farmers are glad when the wet season begins. There is water for their fields and they can again start growing rice. But people in town are not so glad for the streets soon get muddy and dirty. They prefer the dry seasons when they can sit outside and enjoy the cool evenings. 41. When is the wet season ? A. in May. C. from November to May. B. in November. D. from May to November. 42. What causes the rainfall ? A. The ocean. C. The mountains. B. Clouds building up around the mountains. D. The afternoon. 43. Why are many rivers dangerous in the wet season ? A. They dry up and can’t provide enough water. C. People try to cross them B. Long periods of heavy rain make them full. D. They are very big rivers 44. What damages the land ? A. The sudden rain. C. The wet season. B. The overflow of the rivers. D. The dry season. 45. Why can farmers start growing rice again ? A. The dry season has begun. C. There is water again. B. The land has been damaged. D. The rivers overflow. 46. Why are people in town not so happy ? A. They can sit outside. C. The evenings are cool. B. They are muddy and dirty. D. The streets are full of mud giúp mk vs ạ camon nhìuuuuuuu