The five numbers 2, 2, 3, 4, 7 and 5 make up the largest number () and the smallest number ().
3. Starting from one digit, the seventh digit is (), and the counting unit is ().
4.49 □ 785 ≈ 500,000, the maximum amount of □ can be filled in ().
5. When calculating 2 160 ÷ 20-57 with a calculator, press 2 160 on the keyboard, then press ÷, then press 20, and then press ÷-to display the screen ().
6. Five digits are rounded to10,000, and the digit is 80,000. The maximum value of this five-digit number is () and the minimum value is ().
7. "Little careless" miscalculated 28×(□+2) as 28×□+2, so the result is different from the correct answer ().
8.□÷2 1 = 35 ...△, where the maximum value is (), then □ is ().
9. There is a seven-digit number, and the number of digits of each number is 5. If you add 2 to this number, you will get a new seven-digit number. At this point, the sum of digits in this new number is 3, and the original number is ().