The industry demand in for plumbers is given by the equation W = 50-0.08L, and there is a fixed supply of 300 qualified plumbers.
(a) Draw a diagram illustrating the supply, demand and equilibrium.
(b) Solve the supply and demand equations for the equilibrium wage, W.
(c) If the plumbers now form a union, and supply their labour at a wage of $30 per hour, illustrate the new equilibrium on your diagram and calculate the new level of employment.