Companies make sacrifices known as expenses to obtain benefits called revenues. The accurate measurement of net income requires that expenses be matched with revenues. In some circumstances, matching a particular expense directly with revenue is difficult or impossible. In these circumstances, the expense is matched with the period in which it is incurred.

Required
a. Identify an expense that could be matched directly with revenue.
b. Identify a period expense that would be difficult to match with revenue. Explain why.