Giúp em 7 câu dưới với ạ, em xin cảm ơn rất nhiều 13. Global warming occurs when the ……….in the atmosphere trap the heat from the sun. A. greenhouse gases B. infectious deseases C. emissions D. heat-related illnesses 14. Scientists are concerned……….the effects of global warming. A. for B. about C. to D. at 15. As global temperatures rise, there are more cases of ………….. . A. emissions B. climate changes C. heat-related illnesses D. infectious deseases 16. …………….a stable ecosystem in which a large number of species live together. A. Carbon footprint B. Global warming C. Greenhouse gas D. Ecological balance 17. A large amount of carbon dioxide…………..are released into the atmosphere by burning fossil fuels. A. emissions B. infectious deseases C. heat-related illnesses D. Climate changes 18. ………..the content, we are now looking for supporting information. A. To plan B. Having planned C. After we have planned D. B&C 19. Although global warming is causing changes in weather patterns, it is only one aspect of……. . A. global warming B. climate change C. infectious desease D. greenhouse gas 20. The police suspected John ……..having cut down the oldest tree in the park. A. of B. at C. with D. without