帮我讲解下这道题---**Extraction Content:** **Question Stem:** 练习 4 在方框中填写合适的数字，使下列竖式成立。 (Exercise 4 Fill in the appropriate numbers in the boxes to make the following vertical calculation true.) **Chart/Diagram Description:** * Type: Long division vertical calculation diagram. * Main Elements: * Divisor: 49. The digit 9 is inside a box. * Dividend: A 5-digit number with the first two digits represented by boxes, followed by 547. The structure is [box] [box] 5 4 7. * Quotient: A 3-digit number with the first digit 1, the second digit in a box, and the third digit 9. The structure is 1 [box] 9. * Below the first two digits of the dividend, the number 49 is written, aligned vertically. A horizontal line is below 49. * Below the first horizontal line, shifted two places to the right (starting under the 5 of the dividend), is a number represented as 4 [box] [box] 7. A horizontal line is below this number. * Below the line 4 [box] [box] 7, a number represented as [box] [box] [box] is written, aligned under the first three digits of 4 [box] [box] 7. A horizontal line is below this number. * Below the second horizontal line, the remainder 0 6 is written, aligned under the last two digits of the number [box] [box] [box]. **Filled Boxes (based on solving the long division):** By solving the long division 93547 ÷ 49 = 199 with a remainder of 6, the boxes can be filled as follows: * Divisor: 4 [9] * Dividend: [9] [3] 5 4 7 * Quotient: 1 [9] 9 * Line below first subtraction (represented as 4 [box] [box] 7): This line in the diagram corresponds to the partial dividend for the step where the quotient digit is 9. In the correct calculation, the partial dividend leading to the remainder 6 is 447. So, the boxes in "4 [ ] [ ] 7" are 4 and 4. The number is 447. * First box after 4: [4] * Second box after 4: [4] * Line below 4 [box] [box] 7 (represented as [box] [box] [box]): This number is 49 multiplied by the quotient digit 9 in the last step, which is 441. So, the boxes are 4, 4, and 1. * First box: [4] * Second box: [4] * Third box: [1] Therefore, the numbers to be filled in the boxes are: * Divisor: 9 * Dividend: 9, 3 * Quotient: 9 * Line "4 [ ] [ ] 7": 4, 4 * Line "[ ] [ ] [ ]": 4, 4, 1