A: the independent variable is the number of soccer games you officiate
B: the dependent variable is your earnings
C: e = earnings; s = soccer games
e = 15s
15 has prime factors of 5,3
21 has prime factors of 7,3
35 has prime factors of 7,5
105 has prime factors of 7,5,3
315 has prime factors of 7,5,3,3
hope this helps