<image>The education department conducted a sample analysis of a math mock exam for all junior high school graduates in the city before the high school entrance examination. The sample scores were divided into five groups, A, B, C, D, and E, based on score segments (each group includes the minimum score but not the maximum score except for group A). The results were then presented in the two statistical charts below. Based on the information in the charts, please answer the following questions:
(1) The central angle degrees of the C group in the pie chart;
(2) What is the sample size?
(3) The number of students scoring above 84 points;
(4) If there are 3,500 junior high school graduates in the city this year, use this sample survey statistical information to estimate how many students in the city scored above 108 points in this math mock exam.
