Firms in the patented pharmaceutical industry earned an average return on net worth of 22 percent in 2006, compared with an average return of 14 percent earned by over 1,400 firms followed by Value Line.

Which theories of profit do you think explain the performance of the drug industry? Check all that apply.

Risk-bearing theory of profit

Innovation theory of profit

Managerial efficiency theory of profit

Monopoly theory of profit

Temporary disequilibrium theory of profit