GHi dap an 1.If we copy the letters “MATHS” repeatedly, we get “MATHSMATHS. . . ”. What is the 2021-th letter from the left? A A B T C M D.S cau 2: Find the greatest divisor, other than the number itself, of 79680 A 39820 B 39830 C 39840 D 39850 cau 3:What is value of (2 + 4 + 6 + ⋯ + 18) × (1 + 3 + 5 + ⋯ + 19) A 18000 B 28800 C 9000 D 36000 cau 4: Find the units digit of 1997^2021 A 7 B 1 C 9 D 3 Cau 5: The elder sister is 15 years old, the younger sister is 12 years old and brother is 7 years old. Their birthdays are in the same day. When the sum of their ages equal 58, what is the age of the brother? A 13 B 16 C 14 D 15