If Your Cell Phone Bill Is $40 When You Use

question 97

Multiple Choice

If your cell phone bill is $40 when you use up to 300 minutes per month or $80 when you use between 300 and 400 minutes per month, the marginal cost of the 301st minute is:

• A) $0.13.
• B) $0.27.
• C) $40.
• D) $80.