We study the problem of a policy maker who is trying to determine the output gap during the pandemic. Some (but not all) of the questions in this problem may be harder than the rest of the exam. We will assume that actual output is produced using the production function Yt = AtK L 1 t , (3.1) where At is unobserved TFP, K is a known level of capital (which we will keep fixed for simplicity), and Lt is the number of workers actually working. On the other hand, potential output is defined as Yt = AtK