What tax return reporting procedures must be followed by an employee under the following circumstances? a. Expenses

Question:

What tax return reporting procedures must be followed by an employee under the following circumstances?
a. Expenses and reimbursements are equal under an accountable plan.
b. Reimbursements at the appropriate Federal per diem rate exceed expenses, and an adequate accounting is made to the employer.
c. Expenses exceed reimbursements under a non-accountable plan?