Đáp án chỉ để tham khảo vẫn có thể sai: 1a, 2c, 3b, 4c, 5b, 6c, 7a, 8c, 9c, 10b, 11a, 12a, 13d, 14c, 15b, 16b, 17b, 18a, 19b, 20c, 21a, 22a, 23c, 24b, 25b, 26c, 27a, 28c, 29d, 30a, 31c, 32c, 33d, 34d, 35c, 36c, 37d, 38b, 39d, 40d, 41c, 42c, 43b, 44a, 45c, 46a, 47c, 48d, 49c, 50c. Source: OSG202...