(a)[12]
In some industries the wage rate is frequently left out when a job is advertised. Explain the role of the marginal revenue product in setting the wage rate in a perfectly competitive firm and consider whether the labour market is likely to be perfect or imperfect if the wage rate is not stated in an advertisement.
(b)[13]
Discuss, with the help of a diagram, whether a trades union can raise the wage rate of its members without causing employment to fall.