Spencer and Church is a CPA firm engaged in local practice. Some selected items from its chart of accounts are listed here.

REQUIRED
For each account, indicate whether the account represents a fixed, variable, or mixed cost for the operations of the local practice office. If mixed, indicate whether it is predominantly fixed or variable. Explain your answers.
A. Staff wages
B. Clerical wages
C. Rent
D. Licenses
E. Insurance
F. Office supplies
G. Professional dues
H. Professional subscriptions
I. FICA taxes (Social Security taxes)
J. Property taxes
K. Advertising