I need detailed help with steps and calculations on why answer was what it was :

The employees of the City of Raymond earn vacation compensation that totals $1,500 per week. During 2011, $30,000 in vacation time was taken and the remainder is expected to be used during the latter part of next year. In the government-wide financial statements, assuming there was no beginning balance, what liability should be reported at the end of 2011? A. $0. B. $1,500. C. $30,000. D. $48,000. E. $78,000.

*Show exactly how 48,000 was calculated and explain the logic*