Butterfield's bookkeeping service company began operation on jan 1 2016

the following information is taken fron its accounting records as of Dec 31 2016

Bookkeeping service revenue 80,000

bookkeeping salaries 42,000

Bookkeeping office rent 12,000

Depreciation on bookkeeping equipment 700

Advertising 800

a what is the cost of service provided?

b prepare a single step income statement for butterfiled's bookkeeping service for 2016