1. The problem is to solve the Sudoku puzzle by filling in the missing numbers so that each row, column, and 3x3 block contains all digits from 1 to 9 without repetition. 2. Sudoku rules: - Each row must have the numbers 1 to 9 without repeats. - Each column must have the numbers 1 to 9 without repeats. - Each 3x3 block must have the numbers 1 to 9 without repeats. 3. To solve, look for cells where only one number can fit based on the existing numbers in the same row, column, and block. 4. For example, the highlighted cell (row 9, column 7) must be filled with a number that is not already in row 9, column 7, or the bottom-right 3x3 block. 5. By checking the numbers already present, the missing number for that cell is 1. 6. Continue this process for all empty cells until the grid is complete. Final answer: The highlighted cell (row 9, column 7) is 1.