If the median of the following data is 32.5, find the missing frequencies.

Class Interval: 0-10 10-20 20-30 30-40 40-50 50-60 60-70
Total Frequency: f1 5 9 12 f2 3 2 40

a) f1 = 5, f2 = 35
b) f1 = 10, f2 = 30
c) f1 = 15, f2 = 25
d) f1 = 20, f2 = 20