Gợi ý giải 1D-2B-3B-4D-5D-6A-7C-8D-9B-10B 11B-12C-13B-14C-15D-16A-17A-18C-19B-20C 21C-22B-23B-24D-25A-26D-27A-28C-29D-30A 31A-32C-33A-34D-35A-36C-37D-38A-39A-40B 41D-42C-43A-44C-45D-46C-47D-48A