Is each of the following method identifiers (a) legal and conventional, (b) legal but unconventional, or (c)

Question:

Is each of the following method identifiers (a) legal and conventional, (b) legal but unconventional, or (c) illegal?
a. associationRules()
b. void()
c. Golden Retriever()
d. invoice#()
e. 36542ZipCode()
f. PayrollApp()
g. getReady()
h. 911()
i. displayTotal()
j. Accounts_Receivable()