An Internet Service Provider Requires Customers to Prepay for Six

An internet service provider requires customers to prepay for six months of service. On August 1, 2010, Ricky Roberts paid $480 for internet service for the next six-month period. For the year ended December 31, 2010, how much revenue will the internet service have earned from Roberts?

A) $ 0
B) $ 80
C) $320
D) $400
E) $480