Should all professors be paid the same?

The graphs here show the supply of and demand for assistant professors in history $($left$)$ and in biology $($right$)$ for a hypothetical university. Use the graphs to help you answer the following questions.

Market for Assistant History Professors

$0$

$7$

$14$

$21$

$28$

$35$

$42$

$49$

$56$

$63$

$70$

$120$

$108$

$96$

$84$

$72$

$60$

$48$

$36$

$24$

$12$

$0$

SALARY $($Thousands of dollars$)$

QUANTITY $($Assistant history professors$)$

Demand

Supply

Market for Assistant Biology Professors

$0$

$4$

$8$

$12$

$16$

$20$

$24$

$28$

$32$

$36$

$40$

$180$

$162$

$144$

$126$

$108$

$90$

$72$

$54$

$36$

$18$

$0$

SALARY $($Thousands of dollars$)$

QUANTITY $($Assistant biology professors$)$

Demand

Supply

The equilibrium wage of an assistant professor in history is

$$72$

$,$ and the equilibrium quantity is

$28$

assistant professors in history. On the other hand, the equilibrium wage of an assistant professor in biology is

$$108$

$,$ and the equilibrium quantity is

$16$

assistant professors in biology.

Suppose the university sets the same wage for all assistant professors in each department. Fill in the following table with the quantity demanded and supplied for each type of assistant professor when the university sets the wage to $$72,000$ and $$108,000,$ respectively.

University Wage

Assistant History Professors

Assistant Biology Professors

$($Dollars$)$

Quantity Demanded

Quantity Supplied

Shortage or Surplus

Quantity Demanded

Quantity Supplied

Shortage or Surplus

$72,000$

$108,000$

In summary, if the university sets a wage of $$72,000$ for all assistant professors in every department, which is equivalent to a price ceiling for biology professors, there will be

assistant biology professors hired by the university than there would be if the university paid assistant biology professors their equilibrium wage. Similarly, if the university sets a wage of $$108,000$ for all assistant professors in every department, which is equivalent to a price floor for history professors, there will be

assistant history professors hired by the university than there would be if the university paid assistant history professors their equilibrium wage.