One ticket to a show costs \$ 20 at full price. Susan buys 4 tickets using a coupon that gives her a 25 \% discount. Pam buys 5 tickets using a coupon that gives her a 30 \% discount. How many more dollars does Pam pay than Susan?
Answer Choices
A. 2
B. 5
C. 10
D. 15
E. 20