29. The circle graph shows the relative size of each grade (9, 10, 11, and 12) in a high school. Grade ? a) If the school has 900 students in all, calculate the number Grade 10 30% 35% of students in each grade. (2 marks) Grade 11 Grade 12 20% 15% Grade 9 315 Grade 10 270 Grade 11 180 Grade 12 135 b) Construct a new circle graph to show the proportion of Grade 9 students increasing by 10% and the proportion of Grade 11 students decreasing by 10% the following year. (2 marks)