The demand function for flu shots in the U.S. been calculated to be P = 10-0.02Q where P is price of a flu shot and Q is the number of flu shots (in millions per year). Researchers at the NIH calculate that flu immunizations impose a benefit on the rest of society of $1 per flu shot. Flu shots have a constant marginal cost of production of $3 per shot. What is the deadweight loss associated with the positive externality?