The existence of unemployment

a. Suppose the unemployment rate is very low. How easy is it for firms to find workers to hire? How easy is it for workers to find jobs? What do your answers imply about the relative bargaining power of workers and firms when the unemployment rate is very low? What do your answers imply about what happens to the wage as the unemployment rate gets very low?

b. Given your answer to part (a), why is there unemployment in the economy? (What would happen to real wages if the unemployment rate were equal to zero?)