1. The problem is to create a line graph showing the number of students in grades 7 to 10. 2. The categories (grades) are 7, 8, 9, and 10, and the frequencies (number of students) are 80, 95, 100, and 85 respectively. 3. To plot a line graph, we place the grades on the x-axis and the number of students on the y-axis. 4. The points to plot are (7, 80), (8, 95), (9, 100), and (10, 85). 5. Connect these points with straight lines to form the line graph. 6. This graph visually shows how the number of students changes across grades 7 to 10. Final answer: The line graph is represented by the function $$y = f(x)$$ where $$x$$ is the grade and $$y$$ is the number of students, with points at (7,80), (8,95), (9,100), and (10,85).