he following graph shows the labor market for research assistants in the fictional country of Collegia. The equilibrium wage is $10 per hour, and the equilibrium number of research assistants is 200.

Suppose the government has decided to institute a $4-per-hour payroll tax on research assistants and is trying to determine whether the tax should be levied on the employer, the workers, or both (such that half the tax is collected from each side).